lesswrong sequences volume 1.0

7/27/2019 Lesswrong Sequences volume 1.0

http://slidepdf.com/reader/full/lesswrong-sequences-volume-10 1/309

LessWrong.com Sequences

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Generated by lesswrong_book.py on 2013-01-05. Pseudo-random version string: ee78df8a-6178-4d00-8a06-16a9ed81a6be.



A collection of posts dealing with the fundamentals of rationality: the difference between the map and the

territory, Bayes’s Theorem and the nature of evidence,why anyone should care about truth, and minds as

reflective cognitive engines.

Part I

Map and Territory

1. The Simple Truth

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2. What Do We Mean By “Rationality”?

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Epistemic rationality 9<C@<M@E>8E;LG;8K@E>FE<M@;<E:<JF8JKFJPJK<D8K@:8CCP@DGIFM<K?<:FII<JGFE;<E:<9<KN<<E PFLID8G8E;K?<K<II@KFIP /?<8IKF=F9K8@E@E>9<C@<=JK?8K:FII<JGFE;KFI<8C@KP8J:CFJ<CP8JGFJJ@9C< /?@J:FII<JGFE;<E:<@J:FDDFECP K<ID<;`KILK?aFI`8::LI8:Pa8E;N<cI<?8GGPKF:8CC@KK?8K

Instrumental rationality 8:?@<M@E>PFLIM8CL<J Not

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/F B<<G @K K<:?E@:8C PFL NFLC; J8P K?8K K?@J GIF989@C@KP AL;>eD<EK @J non-Bayesian. <C@<=J K?8K :FE=FID KF 8 :F?<I<EK GIF989@C@KP ;@JKI@9LK@FE 8E; ;<:@J@FEJ K?8K D8O@D@Q< K?< GIF989@C@JK@: <OG<:K8eK@FEF=8:F?<I<EKLK@C@KP=LE:K@FE8I<:8CC<;`8P<J@8Ea

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http://lesswrong.com/lw/31/what_do_we_mean_by_rationality/

+8><b/?<.@DGC</ILK?c http://lesswrong.com/lw/ji/conjunction_fallacy/

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http://www.anthropic-principle.com/primer.html http://lesswrong.com/lw/nc/newcombs_problem_and_regret_of_rationality/ +8><b/?<+8I89C<F=#<DCF:Bc

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http://yudkowsky.net/virtues/

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3. An Intuitive Explanation of Bayes'Theorem

Bayes’ Theorem for the curious and bewildered; an excruciatingly gentle introduction.

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http://yudkowsky.net/rational/bayes

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Fun Fact!

Q. What is the Bayesian Conspiracy?A. /?<8P<J@8EFEJG@I8:P@J8 DLCK@E8K@FE8C@EK<I;@J:@GC@E8IP8E;

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Fun Fact!

Q. How can I find the priors for a problem?A. (8EP:FDDFECPLJ<;GI@FIJ8I<C@JK<;@EK?< Handbook of Chemistry and Physics.

Q. Where do priors originally comefrom?A. )<M<I8JBK?8KHL<JK@FE

Q. Uh huh. Then where do scientistsget their priors?A. +I@FIJ=FIJ:@<EK@=@:GIF9C<DJ8I<<JK89C@J?<;9P8EEL8CMFK<F=K?<. $E

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Q. Suppose that there are two barrels,each containing a number of plasticeggs. In both barrels, some eggs arepainted blue and the rest are paintedred. In the first barrel, 90% of theeggs contain pearls and 20% of thepearl eggs are painted blue. In thesecond barrel, 45% of the eggs contain

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%(&,**!,'*1

*E:<K?<;<I@M8K@FE@J=@E@J?<;8CCK?<@DGC@:8K@FEJFEK?<I@>?KJ@;<F=K?<<HL8K@FE8I<F=K?<=FID D0P FI D0PRN?@C<K?<@DGC@:8K@FEFEK?<C<=KJ@;<@J DP0 JCFE>8JPFL

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/?<JPDD<KIP8I@J<J9<:8LJ<K?<<C<D<EK8IP causal relations 8I< ><E<I8CCP@DGC@:8K@FEJ=IFD=8:KJKFF9J<IM8K@FEJ@<=IFD9I<8JK:8E:<IKFGFJ@K@M<D8DDF>I8G?P /?<<C<D<EK8IP steps in reasoning 8I<><E<I8CCP@DGC@:8K@FEJ=IFDF9J<IM8K@FEJKF=8:KJ@<=IFD8 GFJ@K@M<D8DDF>I8G?PKF9I<8JK:8E:I8G?PKFK?<:FE:CLJ@FEF=8E@E:I<8J<;GIF989@C@KPF=9I<8JK:8E:?KeKFeC<=KJF

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*B8PN<cI<;FE<

Reverend Bayes says:

&! &,-!,!.0($&,!'&'1+,'*%



You are now an initiateof the Bayesian Conspiracy.

%(&,**!,'*1

4. Why truth? And…

.FD< F= K?< :FDD<EKJ @E K?@J 9CF> ?8M< KFL:?<; FE K?< HL<JK@FE

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@K @J M<IP @DGFIK8EK KF ;@JK@E>L@J? K?8K ;@:?FKFDP =IFD Ì8K@FE8C@eKPa FK? JPJK<DJ :8E J<IM< K?< >F8C F= KILK? FI ;<=<8K @K 8::FI;@E> KF?FNK?<P8I<LJ<;

<J@;<J J?< KILK? 2<CC PFL D@>?K N8EK KF 8::FDGC@J? JFD< JG<e:@=@: I<8CeNFIC; >F8C C@B< 9L@C;@E> 8E 8@IGC8E< 8E; K?<I<=FI< PFLE<<; KF BEFN JFD< JG<:@=@: KILK? 89FLK 8<IF;PE8D@:J *I DFI<DLE;8E<CP PFL N8EK :?F:FC8K< D@CB 8E; K?<I<=FI< PFL N8EK KF

http://lesswrong.com/lw/go/why_truth_and/ http://sl4.org/wiki/TheSimpleTruth

$ K<E; KF 9< JLJG@:@FLJ F= DFI8C@KP 8J 8 DFK@M8K@FE =FI I8K@FeE8C@KP not 9<:8LJ< $ I<A<:K K?< DFI8C @;<8C 9LK 9<:8LJ< @K @EM@K<J:<IK8@E B@E;J F= KIFL9C< $K @J KFF <8JP KF 8:HL@I< 8J C<8IE<; DFI8C

;LK@<J DF;<J F= K?@EB@E> K?8K 8I< ;I<8;=LC D@JJK<GJ @E K?< ;8E:<FEJ@;@M<J D8EP J@>E@=@:8EK ;@>@KJ =FI GIF989@Ce@K@<J K?8K 8I< >IFJJCP LE:8C@9I8K<; h> `8GK8@E @= PFL JK< @J FECP na 4<K E@E< K@D<J FLK F= K<E K?< EK<IGI@J< @J EFK ;<eJKIFP<; 2?8K B@E; F= KI8>@: =FFC >@M<J =FLI J@>E@=@:8EK ;@>@KJ =FI 8 =@>LI< K?8K @J F== 9P KNF FI;<IJ F= D8>E@KL;< @J ?FN D8EP G<FGC< :FE:<@M< F= K?< ;LKP KF 9< `I8K@FE8CagJD8CC NFE;@M< @K 8CC K?< ;I<8;=LC ;<>I<<J F= =I<<;FD F= 8E 8I9@KI8IP KI@98C :LJKFD +<FGC< 8II@M< 8K K?< NIFE> 8EJNE8EKCP GIFK<JK K?8K K?=IFDK?<@ID@JK8B<

E; P<K @= N<cI< >F@E> KF improve FLI JB@CCJ F= I8K@FE8C@KP >F 9<e PFE; K?< JK8E;8I;J F= G<I=FID8E:< J<K 9P ?LEK<Ie>8K?<I<IJ N<cCCE<<; ;<C@9<I8K< 9<C@<=J 89FLK ?FN KF K?@EB N@K? GIFGI@<KP 2?<E

N< NI@K< E<N D<EK8C GIF>I8DJ =FI FLIJ<CM<J K? K?8K N< =@E; N< N8EK KF avoid gC@B< J8P9@8J<Jg@K N@CC <E; LG I<GI<J<EK<; N@K?@E .PJK<D 8J 8E @EALE:K@FEEFKKFK?@EBK?8KN8P8GIF=<JJ<;;LKPF=8MF@;8E:<

$= N< N8EK K?< KILK? N< :8E DFJK <==<:K@M<CP F9K8@E @K 9P K?@EBe@E> @E :<IK8@E N8PJ I8K?8:<IK8@E:C8JJF=F9JK8:C<JK?<9@8J<J_

hFEK@EL<;@EE<OKGFJK `2?8KcJ89@8J8>8@Eai

/1,*-, &3

5. What is Evidence?

`/?<J<EK<E:<bJEFN@JN?@K<c@J true @=8E;FECP@=JEFN@J

N?@K<a gC=I<;/8IJB@

`/FJ8PF=N?8K@JK?8K@K@JFIF=N?8K@JEFKK?8K@K@JEFK@J true.a

gI@JKFKC< Metaphysics IV

$= K?<J< KNF HLFK<J ;FEcK J<<D C@B< 8 JL==@:@<EK ;<=@E@K@FE F= `KILK?aI<8; K?@J /F;8P $cD >F@E> KF K8CB 89FLK `<M@;<E:<a h$ 8CJF @EK<E;KF ;@J:LJJ 9<C@<=JeF=e=8:K EFK <DFK@FEJ FI DFI8C@KP 8J ;@JK@E>L@J?<;?<I 8CFE> K?< JKI<<K PFLI J?F<C8:<J :FD< LEK@<; .?FIKCP K?<I<8=K?K C<8M<J K?< .LE 8E; JKI@B<J PFLI J?F<C8:<J 8E;9FLE:<J F== JFD< G?FKFEJ <EKP F= K?< G?FKFEJ KI@>><IJ E<LI8C @DGLCJ<J K?<E<LI8C @DGLCJ<J 8I< KI8EJD@KK<; KF K?< M@JL8CeGIF:<JJ@E> 8I<8J F= K?<9I8@E 8E; K?<I< K?< FGK@:8C @E=FID8K@FE @J GIF:<JJ<; 8E; I<:FEe

JKIL:K<; @EKF 8 DF;<C K?8K @J I<:F>E@Q<; 8J 8E LEK@<; J?F<C8:</?<I< @J 8 J<HL<E:< F= <M<EKJ 8 :?8@E F= :8LJ< 8E; <==<:K N@K?@EK?< NFIC; 8E; PFLI 9I8@E 9P N?@:? PFL <E; LG 9<C@<M@E> N?8K PFL9<C@<M< /?< =@E8C FLK:FD< F= K?< GIF:<JJ @J 8 JK8K< F= mind N?@:?D@IIFIJK?<JK8K<F=PFLI8:KL8C shoelaces

2?8K @J evidence? $K @J 8E <M<EK <EK8E>C<; 9P C@EBJ F= :8LJ<8E; <==<:K N@K? N?8K<M<K F=

PFLI @EHL@IP @J PFLI J?F<C8:<J =FI <O8DGC< K?<E K?< C@>?K <EK<I@E> PFLI GLG@CJ @J <M@;<E:< <EK8E>C<; N@K? PFLI J?F<C8:<J /?@J J?FLC;

EFK 9< :FE=LJ<; N@K? K?< K<:?E@:8C J<EJ< F= `<EK8E>C<D<EKa LJ<; @EG?PJ@:Jg?<I< $cD ALJK K8CB@E> 89FLK `<EK8E>C<D<EKa @E K?< J<EJ< F= KNF K?@E>J K?8K <E; LG @E :FII<C8K<; JK8K<J 9<:8LJ< F= K?< C@EBJ F= :8LJ<8E;<==<:K9<KN<<EK?<D

)FK <M<IP @E=CL<E:< :I<8K<J K?< B@E; F= `<EK8E>C<D<EKa I<HL@I<;=FI <M@;<E:< $KcJ EF ?<CG KF ?8M< 8 D8:?@E< K?8K 9<<GJ N?<E PFL<EK CFKK<IP ELD9<IJ @= K?< D8:?@E< also 9<<GJ N?<E PFL

http://lesswrong.com/lw/jl/what_is_evidence/

http://sl4.org/wiki/TheSimpleTruth +8><b!<<C@E>-8K@FE8Cc

<==<:K 2?<E PFL J8P `(P J?F<C8:<J 8I< LEK@<;a FM PFLI <EK8E>C<D<EK N@K? PFLI J?F<C8:<J N@K? 8 =I@<E;

/?<I<=FI< I8K@FE8C 9<C@<=J 8I< :FEK8>@FLJ 8DFE> ?FE<JK =FCB

N?F 9<C@<M< <8:? FK?@FLJgK?8K PFL 9<C@<M< =FI GI@M8K< I<8JFEJ N?@:? 8I< EFK KI8EJD@JJ@9C<g@J JF JLJG@:@FLJ $= PFLI 9<C@<=J 8I< <EeK8E>C<;N@K?I<8C@KPK?@FLJ8DFE>?FE<JK=FCB

$= PFLI DF;<C F= I<8C@KP JL>><JKJ K?8K K?< FLKGLKJ F= PFLIK?FL>?K GIF:<JJ<J J?FLC; not 9< :FEK8>@FLJ KF FK?<IJ K?<E PFLIDF;<C J8PJ K?8K PFLI 9<C@<=J 8I< EFK K?<DJ<CM<J <M@;<E:< D<8E@E> K?C<; N@K? I<8C@KP 4FL J?FLC; 8GGCP 8 I<=C<:K@M<:FII<:K@FE8E;JKFG9<C@<M@E>

$E;<<; @= PFL feel, FE 8 gut C<M<C N?8K K?@J 8CC means, PFL N@CC automatically JKFG 9<C@<M@E> <:8LJ< `DP 9<C@<= @J EFK <EK8E>C<; N@K? I<8C@KPa means `DP 9<C@<= @J EFK 8::LI8K<a J JFFE 8J PFL JKFG9<C@<M@E> `bJEFN @J N?@K<c @J KIL<a PFL J?FLC; h8LKFD8K@:8CCPi JKFG9<C@<M@E>`JEFN@JN?@K<aFIJFD<K?@E>@JM<IPNIFE>

.F >F 8?<8; 8E; <OGC8@E N?P K?< B@E; F= K?FL>?K GIF:<JJ<J PFLLJ< JPJK<D8K@:8CCP GIF;L:< 9<C@<=J K?8K D@IIFI I<8C@KP OGC8@E N?P

PFL K?@EB PFLcI< rational. 2?P PFL K?@EB K?8K LJ@E> K?FL>?K GIFe

:<JJ<J C@B< K?< FE<J PFL LJ< D@E;J N@CC <E; LG 9<C@<M@E> `JEFN @J N?@K<a @= 8E; FECP @= JEFN @J N?@K< $= PFL ;FEcK 9<C@<M< K?8K K?<FLKGLKJ F= PFLI K?FL>?K GIF:<JJ<J 8I< <EK8E>C<; N@K? I<8C@KP N?P ;F PFL 9<C@<M< K?< FLKGLKJ F= PFLI K?FL>?K GIF:<JJ<J $KcJ K?< J8D<K?@E>FI@KJ?FLC;9<

%(&,**!,'*1

6. How Much Evidence Does It Take?

Followup to: 2?8K@JM@;<E:<

+I<M@FLJCP $ ;<=@E<; evidence 8J `8E <M<EK <EK8E>C<; 9P C@EBJ F= :8LJ< 8E; <==<:K N@K? N?8K<M ;@==<I<EKCP =FI ;@==<I<EK GFJJ@9C< JK8K<J F= K?<K8I><Ka .F ?FN DL:? <EK8E>C<D<EKg?FN DL:? <M@;<E:<g@J I<eHL@I<;KFJLGGFIK89<C@<=

'<KcJ JK8IK N@K? 8 HL<JK@FE J@DGC< <EFL>? KF 9< D8K?<D8K@:8C?FN ?8I; NFLC; PFL ?8M< KF <EK8E>C< PFLIJ<C= N@K? K?< CFKK<IP

@E FI; :FD9@E8K@FEJ ?<E:< 8 I8E;FDCP J<C<:K<; K@:B<K NFLC; ?8M< 8 GIF989@C@KP F= N@EE@E> hni /F N@E K?< CFKK<IP PFL NFLC; E<<; <M@;<E:< selective <EFL>? KF M@J@9CP =8MFI FE< :FD9@E8K@FE FM 8E; CFJ@E> CFKK<IP ELDe9<IJ !FI <O8DGC< PFL :8E GLE:? 8 :FD9@E8K@FE @EKF 8 C@KKC< 9C8:B

9FO K?8K 8CN8PJ 9<<GJ @= K?< :FD9@E8K@FE @J K?< N@EE @= K?< :FD9@E8K@FE @J NIFE>$E 8P<J@8E K<IDJ N< NFLC; J8P K?< likelihood ratio @J KF /?@JD<8EJ K?8K K?< 9FO @J K@D<J 8J C@B<CP KF 9<<G N?<E N< GLE:? @E8 :FII<:K :FD9@E8K@FE :FDG8I<; KF ?FN C@B<CP @K @J KF 9<<G =FI 8E@E:FII<:K:FD9@E8K@FE

/?<I< 8I< JK@CC 8 N?FC< CFK F= GFJJ@9C< :FD9@E8K@FEJ $= PFLGLE:? @E @E:FII<:K :FD9@E8K@FEJ K?< 9FO N@CC 9<<G FE F= K?<D

9P J?< :FD9@E8K@FE @K N@CC 8CJF 9<<G =FI CFJ@E> :FD9@eE8K@FEJhFE8M<I8> $= PFL LJ<; K?< 9FO PFLI F;;J F= N@EE@E> NFLC; >F =IFD

http://lesswrong.com/lw/jn/how_much_evidence_does_it_take/ +8><b2?8K@JM@;<E:<c +8><b2?8K@JM@;<E:<c

http://lesswrong.com/lw/hl/lotteries_a_waste_of_hope/ +8><bE$EKL@K@M<OGC8E8K@FEF=8P<J/?<FI<Dc

@E KF @E 4FLcM< D8;< JFD< GIF>I<JJ KFN8I;=@E;@E> PFLI K8I><K K?< KILK? N@K?@E K?< ?L>< JG8:< F= GFJJ@9@C@K@<J

.LGGFJ< PFL :8E LJ< 8EFK? K@:B<K LK K?< :?8E:< F= 8 9FO 9<<G@E> =FI 8 CFJ@E> :FD9@E8K@FE @J independently =FI <8:? 9FO ?<E:< K?< :?8E:< F= both 9FO<J 9<<Ge@E> =FI 8 CFJ@E> :FD9@E8K@FE @J 2< :8E J8P K?8K K?< cumulative<M@;<E:< F= KNF @E;<G<E;<EK K<JKJ ?8J 8 C@B<C@?FF; I8K@F F= /?< ELD9 CFKK<IP K@:B<KJ K?8K G8JJ 9FK? K<JKJ N@CC 9< hFE8M<I8>?K >L<JJ K?8K PFL E<<; <M@;<E:< N?FJ< JKI<E>K? @J 8IFLE; KF

g8E <M<EK FI J<I@<J F= <M<EKJ N?@:? @J K@D<J DFI< C@B<eCP KF ?8GG<E =FI 8 N@EE@E> :FD9@E8K@FE K?8E 8 CFJ@E> :FD9@E8K@FE

:KL8CCP K?@J 8DFLEK F= <M@;<E:< NFLC; FECP 9< <EFL>? KF >@M< PFL8E even :?8E:< F= N@EE@E> K?< CFKK<IP 2?P <:8LJ< @= PFL 8GGCP 8 =@CK K@:B<KJ K?<I< N@CC 9< FE8M<I8>< FE< CFJ@E> K@:B<K K?8K G8JJ<J K?< =@CK K@:B<K

N@CC 8CJF G8JJ K?< =@CK @= PFL:8EFECP9LPFE<K@:B<K

9<KK K?< GIF9C<D $E K?< 9<>@EE@E> K?<I< @J N@EE@E> K@:B<K 8E; CFJ@E> K@:B<KJ JF PFLI F;;J F= N@EeE@E> 8I< $= PFL LJ< 8 J@E>C< 9FO K?< F;;J F= @K 9<<G@E> 8I< =FI 8 N@EE@E> K@:B<K 8E; =FI 8 CFJ@E> K@:B<K .F N< DLCK@eGCP 9P 8E; ><K ;;@E> 8EFK?8@E JF EFN K?< F;;J 8I<N@EE@E>K@:B<KKFCFJ@E>K@:B<KJ

$K @J :FEM<E@<EK KF D<8JLI< <M@;<E:< @E 9@KJgEFK C@B< 9@KJ FE

8 ?8I; ;I@M< 9LK D8K?<D8K@:@8EcJ 9@KJ N?@:? 8I< :FE:<GKL8CCP ;@=e=<I<EK (8K?<D8K@:@8EcJ 9@KJ 8I< K?< CF>8I@K?DJ 98J< F= GIF9e89@C@K@<J !FI <O8DGC< @= K?<I< 8I< =FLI GFJJ@9C< FLK:FD<J 8E; N?FJ< GIF989@C@K@<J 8I< n n n 8E; n 8E; $K<CC PFL K?< FLK:FD< N8J `a K?<E $ ?8M< KI8EJD@KK<; K?I<< 9@KJ F= @E=FID8K@FE KF PFL 9<:8LJ< $ @E=FID<; PFL F= 8E FLK:FD< N?FJ<GIF989@C@KPN8J

$K JF ?8GG<EJ K?8K @J JC@>?KCP C<JJ K?8E KF K?< K?GFN<I .F 9FO<J FI 9@KJ F= <M@;<E:<g8E <M<EK

%(&,**!,'*1

K@D<J DFI< C@B<CP KF ?8GG<E @= K?< K@:B<Ke?PGFK?<J@J @J KIL< K?8E@= @K @J =8CJ<gNFLC; J?@=K K?< F;;J =IFD KF N?@:? I<;L:<J KF *;;J F= KF D<8E

KNF :?8E:<J KF N@E =FI <8:? :?8E:< KF CFJ< JF K?< probability F= N@EeE@E> N@K? 9@KJ F= <M@;<E:< @J ;;@E> 8EFK? P<K 8EFK?<IKNF9FO<JNFLC;K8B<K?<:?8E:<F=N@EE@E>KF

.F @= PFL N8EK KF C@:<EJ< 8 strong belief K?8K PFL N@CC N@E K?<CFKK<IPg8I9@KI8I@CP ;<=@E<; 8J C<JJ K?8E 8 n GIF989@C@KP F= 9<@E>

NIFE>g 9@KJ F= <M@;<E:< 89FLK K?< N@EE@E> :FD9@E8K@FE J?FLC;;FK?<KI@:B

$E ><E<I8C K?< ILC<J =FI N<@>?@E> `?FN DL:? <M@;<E:< @K K8B<Ja

=FCCFN 8 J@D@C8I G8KK<IE /?< C8I>?9FIJ FI K?< DFI< :FE=@;<EK PFL N@J? KF9<K?<DFI<<M@;<E:<PFLE<<;

4FL :8EEFK ;<=P K?< ILC<J PFL :8EEFK =FID 8::LI8K< 9<C@<=J98J<; FE @E8;<HL8K< <M@;<E:< '<KcJ J8P PFLcM< >FK 9FO<J C@E<;LG @E 8 IFN 8E; PFL JK8IK GLE:?@E> :FD9@E8K@FEJ @EKF K?< 9FO<J4FL :8EEFK JKFG FE K?< =@IJK :FD9@E8K@FE K?8K ><KJ 9<<GJ =IFD

8CC 9FO<J J8P@E> `LK K?< F;;J F= K?8K ?8GG<E@E> =FI 8 CFJ@E> :FD9@E8K@FE 8I< 8 D@CC@FE KF FE< $cCC ALJK @>EFI< K?FJ< @MFIPeKFN<I8P<J@8E ILC<J 8E; JKFG ?<I<a *E 8M<I8>< CFJ@E> K@:B<KJ N@CCG8JJ JL:? 8 K<JK =FI <M<IP N@EE K?< JG8:< F= GFJeJ@9@C@K@<J 8E; K?< GI@FI @DGIF989@C@KP PFL ALDG<; KF 8 KFFeJKIFE> :FE:CLJ@FE 98J<; FE @EJL==@:@<EK <M@;<E:< /?8KcJ EFK 8 GF@EKC<JJ9LI<8L:I8K@:I<>LC8K@FE@KcJD8K?

*= :FLIJ< PFL :8E JK@CC believe 98J<; FE @E8;<HL8K< <M@;<E:< @= K?8K @J PFLI N?@D 9LK PFL N@CC EFK 9< 89C< KF 9<C@<M< accurately. $K

@J C@B< KIP@E> KF ;I@M< PFLI :8I N@K?FLK 8EP =L<C 9<:8LJ< PFL ;FEcK9<C@<M< @E K?< J@CCPe;@CCP =L;;Pe;L;;P :FE:<GK K?8K @K FL>?K KF K8B<=L<C KF >F GC8:<J $K NFLC; 9< JF DL:? DFI< fun, 8E; JF DL:? C<JJ<OG<EJ@M< @= N< ALJK ;<:@;<; KF I<G<8C K?< C8N K?8K :8IJ E<<; =L<C$JEcK @K ALJK F9M@FLJCP 9<KK LK KF really 8II@M< 8K 8::LI8K< 9<C@<=J I<HL@I<J <M@;<E:<e=Le<C8E;K?<=LIK?<IPFLN8EKKF>FK?<DFI<=L<CPFLE<<;

'/%-.!&'+!,,#

7. How to Convince Me That 2 + 2 = 3

$E`2?8K@JM@;<E:<a$ NIFK<

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@?8E8I8E I<GC@<;

$:8EEFK:FE:<@M<F=8J@KL8K@FEK?8KNFLC;D8B<=8CJ<+<I?8GJ=FIK?8KI<8JFEDP9<C@<=@E@JLE:FE;@K@FE8C

$ 8;D@K $ :8EEFK :FE:<@M< F= 8 `J@KL8K@FEa K?8K NFLC; make =8CJ< h/?<I< 8I< I<;<=@E@K@FEJ 9LK K?FJ< 8I< EFK `J@KL8eK@FEJa 8E; K?<E PFLcI< EF CFE> 89FLK FI i LKK?8K ;F<JEcK D8B< DP 9<C@<= LE:FE;@K@FE8C $ =@E; @K HL@K< <8JP KF@D8>@E<8J@KL8K@FEN?@:?NFLC; convince D<K?8K

.LGGFJ< $ >FK LG FE< DFIE@E> 8E; KFFB FLK KNF <8IGCL>J 8E;J<K K?<D ;FNE E<OK KF KNF FK?J FE DP E@>?KK89C< 8E;EFK@:<; K?8K K?<I< N<I< EFN K?I<< <8IGCL>J N@K?FLK 8EP <8IGCL>J?8M@E> 8GG<8I<; FI ;@J8GG<8I<;g@E :FEKI8JK KF DP JKFI<; D<DFIP K?8K N8J JLGGFJ<; KF <HL8C (FI<FM 33 8E; 33:FD< FLK KF 3333 I<HL@I<; 8E <OKI8 3 KF 8GG<8I =IFD EFN?<I<8E; N8J DFI<FM 33 =IFD 333 C<=K 33 9LK JL9KI8:K@E> 33 =IFD3333 C<=K 333 /?@J NFLC; :FE=C@:K N@K? DP JKFI<; D<DFIP K?8K e 9LK D<DFIP NFLC; 9< 89JLI; @E K?< =8:< F= G?PJ@:8C8E;D<EK8C:FE=@ID8K@FEK?8K333e3333

http://lesswrong.com/lw/jr/how_to_convince_me_that_2_2_3/

+8><b2?8K@JM@;<E:<c http://lesswrong.com/lw/jl/what_is_evidence/f7h

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9. The Lens That Sees Its Flaws

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http://lesswrong.com/lw/i8/religions_claim_to_be_nondisprovable/ http://lesswrong.com/lw/gv/outside_the_laboratory/ http://arxiv.org/abs/astro-ph/0302131

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A sequence on how to see through the disguises of answersor beliefs or statements, that don’t answer or say or mean

anything.

Part II

Mysterious Answers to MysteriousQuestions

1. Making Beliefs Pay Rent (in AnticipatedExperiences)

/?LJ9<>@EJK?<8E:@<EKG8I89C< If a tree falls in a forest and no one hears it, does it make a sound? One

says, “Yes it does, for it makes vibrations in the air.” Another says, “No it does not, for there is no auditory processing in any brain.”

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http://lesswrong.com/lw/i3/making_beliefs_pay_rent_in_anticipated_experiences/

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2. Belief in Belief

Followup to: (8B@E> <C@<=J +8P -<EK h@E EK@:@G8K<; OG<I@e

<E:<Ji

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.FD< G?@CFJFG?<IJ ?8M< 9<<E DL:? :FE=LJ<; 9P JL:? J:<E8I@FJ

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http://lesswrong.com/lw/i4/belief_in_belief/ +8><b(8B@E><C@<=J+8P-<EKh@EEK@:@G8K<;OG<I@<E:<Jic

http://www.godlessgeeks.com/LINKS/Dragon.htm +8><b(8B@E><C@<=J+8P-<EKh@EEK@:@G8K<;OG<I@<E:<Jic

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3. Bayesian Judo

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http://lesswrong.com/lw/i5/bayesian_judo/ +8><b<C@<=@E<C@<=c

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6. Focus Your Uncertainty

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http://lesswrong.com/lw/ia/focus_your_uncertainty/

http://lesswrong.com/lw/i2/two_more_things_to_unlearn_from_school/ http://www.aft.org/pubs-reports/american_educator/issues/summer07/Crit_Thinking.pdf

actly 42 minutes on excuse #3? Why not 41 minutes, or 43? Admit it—you’re not being objective! You’re playing subjective favorites!

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7. The Virtue of Narrowness

What is true of one apple may not be true of another apple; thus more can be

said about a single apple than about all the apples in the world. g/N<CM<1@IKL<JF=-8K@FE8C@KP

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http://lesswrong.com/lw/ic/the_virtue_of_narrowness/

http://yudkowsky.net/virtues/ http://yudkowsky.net/virtues/

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And DON’T EVEN GET ME STARTED on people who thinkWikipedia is an “Artificial Intelligence”, the invention of LSD was a “Sin- gularity” or that corporations are “superintelligent”!

,.!*,-'&**'/&++

8. Your Strength as a Rationalist

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http://lesswrong.com/lw/if/your_strength_as_a_rationalist/

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http://www.overcomingbias.com/2007/08/truth-bias.html http://www.wjh.harvard.edu/%7Edtg/

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9. Absence of Evidence Is Evidence of Absence

!IFD-F9PE8N<JcJ Rational Choice in an Uncertain World

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12. Hindsight Devalues Science

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http://lesswrong.com/lw/im/hindsight_devalues_science/ http://csml.som.ohio-state.edu/Music829C/hindsight.bias.html

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13. Fake Explanations

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+8><b<C@<=8JKK@I<c http://lesswrong.com/lw/i8/religions_claim_to_be_nondisprovable/ +8><b!F:LJ4FLI0E:<IK8@EKPc +8><b4FLI.KI<E>K?8J8-8K@FE8C@JKc +8><b9J<E:<F=M@;<E:<$JM@;<E:<F=9J<E:<c

+8><b#@E;J@>?K<M8CL<J.:@<E:<c +8><bFEJ<IM8K@FEF=OG<:K<;M@;<E:<c

#0($&,!'&+

14. Guessing the Teacher’s Password

Followup to: !8B<OGC8E8K@FEJ

2?<E $ N8J PFLE> $ I<8; GFGLC8I G?PJ@:J 9FFBJ JL:? 8J-@:?8I; !<PED8EcJ QED: The Strange Theory of Light and Matter. $BE<N K?8K C@>?K N8J N8M<J JFLE; N8J N8M<J D8KK8E KF I<8; K?< Feynman Lectures on Physics, $ I8E 8:IFJJ 8 ><D :8CC<; `K?< N8M< <HL8K@FEa $ :FLC; =FCCFN K?< <HL8K@FEcJ ;<I@M8K@FE 9LK CFFB@E> 98:B $ :FLC;EcK J<< @KJ KILK?8K 8 >C8E:< .F $ K?FL>?K 89FLK K?< N8M< <HL8K@FE =FI K?I<< ;8PJ FE

8E; F== LEK@C $ J8N K?8K @K N8J <D98II8JJ@E>CP F9M@FLJ E; N?<E$ =@E8CCP LE;<IJKFF; $ I<8C@Q<; K?8K K?< N?FC< K@D< $ ?8; 8::<GK<;K?< ?FE<JK 8JJLI8E:< F= G?PJ@:@JKJ K?8K C@>?K N8J N8M<J JFLE; N8J

N8M<J D8KKL<JK @;<8 F= N?8K K?< NFI;`N8M<aD<8EKKF8G?PJ@:@JK

/?<I< @J 8E @EJK@E:K@M< K<E;<E:P KF K?@EB K?8K @= 8 G?PJ@:@JK J8PJ`C@>?K @J D8;< F= N8M<Ja 8E; K?< K<8:??K D8;<F=a 8E; K?< JKL;<EK J8PJ `28M<Ja K?< JKL;<EK ?8J D8;< 8 KIL<JK8K<D<EK /?8KcJ FECP =8@I I@>?K 2< 8::<GK `N8M<Ja 8J 8 :FII<:K

8EJN?K

2?@:? @J FE< DFI< 98; ?89@K KF LEC<8IE =IFD J:?FFC 2FI;J;F EFK ?8M< @EKI@EJ@: ;<=@E@K@FEJ $= $ ?<8I K?< JPCC89C<J `9<8eM<Ia8E; K?@EB F= 8 C8I>< IF;<EK K?8K @J 8 =8:K 89FLK DP FNE JK8K< F= D@E; EFK 8 =8:K 89FLK K?< JPCC89C<J `9<8eM<Ia /?< J<HL<E:< F= JPCeC89C<J `D8;< F= N8M<Ja hFI `9<:8LJ< F= ?<8K :FE;L:K@FE`i @J EFK 8 hypothesis, @K @J 8 G8KK<IE F= M@9I8K@FEJ KI8M<C@E> K?IFL>? K?< 8@I FI

@EB FE G8G?K FI NIFE> LK @E J:?FFC K?< K<8:?<I?8E;J PFL 8 >FC; JK8I =FI saying `D8;< F= N8M<Ja N?@:? DLJK 9< K?<:FII<:K 8EJN<b!8B<OGC8E8K@FEJc http://lesswrong.com/lw/hs/think_like_reality/ http://www.math.utah.edu/~pa/math/polya.html

http://lesswrong.com/lw/i2/two_more_things_to_unlearn_from_school/ +8><b!8B<OGC8E8K@FEJc

><KJ K?< >FC; JK8I JKL;<EKJ 9<>@E KF K?@EB K?8K M<I98C 9<?8M@FI ?8J 8 KILK?eM8CL< =K?K @J D8;< F= N8M<J FI @K @JEcK I@>?K

E; K?@J C<8;J @EKF 8E <M<E NFIJ< ?89@K .LGGFJ< K?< K<8:? GIF9C<D @EMFCM@E> 8 D<K8C GC8K< E<OKKF 8 I8;@8KFI K?< =8I J@;< =<<CJ N8ID<KK@E> 8 >FC; JK8Ig@K NFEcK <M<E :FLEK 8J :C8JJ G8IeK@:@G8K@FE LK ;LI@E> K?< :LII<EK J<D<JK<I K?@J K<8:?<I ?8J LJ<;K?< G?I8J<J `9<:8LJ< F= ?<8K :FEM<:K@FEa `9<:8LJ< F= ?<8K :FE;L:eK@FEa 8E; `9<:8LJ< F= I8;@8EK ?<8Ka *E< F= K?<J< @J GIF989CP N?8KK?< K<8:? K?< JPD9FCJ F= K?< ;@==LJ@FE <HL8K@FE hK?< D8K? >FM<IE@E> ?<8K :FE;L:K@FEi ;F<JEcK D<8E PFLcM< =FID<; 8 ?PGFK?e<J@J about K?< D<K8C GC8K< /?@J @J EFK J:?FFC N< 8I< EFK K<JK@E>

PFLI D<DFIP KF J<< @= PFL :8E NI@K< ;FNE K?< ;@==LJ@FE <HL8K@FE/?@J @J 8P<J:I8=K N< 8I< J:FI@E> PFLI 8EK@:@G8K@FEJ F= <OG<I@<E:<$= PFL use K?< ;@==LJ@FE <HL8K@FE 9P D<8JLI@E> 8 =<N GF@EKJ N@K? 8

K?<IDFD<K KF GI<;@:K N?8K K?< K?<IDFD<K flowing, 8E;K?<I<=FI< ?FC;J 8 D8K:? E<8I K?< :FFCF<J K?<E K?@J D<EK8C @D8>< F= =CFN@E>eE<JJ:FEE<:KJKF<OG<I@<E:<@K:FEKIFCJ8EK@:@G8K@FE

$= PFL 8I<EcK using K?< ;@==LJ@FE <HL8K@FEgGLKK@E> @E ELD9<IJ8E; ><KK@E> FLK I<JLCKJ K?8K :FEKIFC PFLI 8EK@:@G8K@FE F= G8IK@:LC8I<OG<I@<E:<JgK?<E K?< :FEE<:K@FE 9<KN<<E D8G 8E; K<II@KFIP @J

J<M<I<; 8J K?FL>? 9P 8 BE@=< 2?8K I<D8@EJ @J EFK 8 9<C@<= 9LK 8 M<I98C9<?8M@FI

$E K?< J:?FFC JPJK<D @KcJ 8CC 89FLK M<I98C 9<?8M@FI N?<K?<KJ PFL 8 >FC; JK8IFI 8 =8@C@E> >I8;< +8IK F= LEC<8IE@E> K?@J 98; ?89@K @J 9<:FD@E>

+8><b!8B<OGC8E8K@FEJc

+8><b<C@<=8JKK@I<c +8><b<C@<=8JKK@I<c

-++!&,,* 6+(++/'*

:FEJ:@FLJCP 8N8I< F= K?< ;@==<I<E:< 9<KN<<E 8E <OGC8E8K@FE 8E; 8 G8JJNFI;

F<J K?@J J<<D KFF ?8IJ? 2?<E PFLcI< =8:<; 9P 8 :FE=LJ@E>

D<K8C GC8K< :8EcK `#<8K :FE;L:K@FEa 9< 8 =@IJK JK<G KFN8I; =@E;@E> K?< 8EJN K?8K PFL 8I< CFFB@E> =FI 8 G8JJNFI; 2?8K @= K?<I< @J EF K<8:?<IKF K<CC PFL K?8K PFL =8@C<; /?<E PFL D8P K?@EB K?8K `'@>?K @J

N8B8C@O<Ja @J 8 >FF; <OGC8E8K@FE K?8K `N8B8C@O<Ja @J K?< :FII<:KG8JJNFI; $K ?8GG<E<; KF D< N?<E $ N8J E@E< P<8IJ FC;gEFK 9<e:8LJ< $ N8J JKLG@; 9LK 9<:8LJ< K?@J @J N?8K ?8GG<EJ by default. /?@J@J ?FN ?LD8E 9<@E>J K?@EB LEC<JJ K?<P 8I< KI8@E<; not KF =8CC @EKFK?< KI8G #LD8E@KP JK8P<; JKL:B @E ?FC<J C@B< K?@J =FI K?FLJ8E;J F=

P<8IJ(8P9< @= N< ;I@CC JKL;<EKJ K?8K words don’t count, only anticipation-

controllers, K?< JKL;<EK N@CC not ><K JKL:B FE `#<8K :FE;L:K@FE )F(8P9< ?<8K :FEM<:K@FE /?8KcJ EFK @K <@K?<Ia (8P9< then, K?@EBe@E> K?< G?I8J< `#<8K :FE;L:K@FEa N@CC C<8; FEKF 8 ><EL@E<CP ?<CG=LCG8K?C@B<

[ `#<8K:FE;L:K@FEa[ LKK?8KcJFECP8G?I8J<gN?8K;F<J@KD<8E

[ /?<;@==LJ@FE<HL8K@FE[ LKK?FJ<8I<FECPJPD9FCJg?FN;F$8GGCPK?<D[ 2?8K;F<J8GGCP@E>K?<;@==LJ@FE<HL8K@FEC<8;D<KF

8EK@:@G8K<[ $KJLI<;F<JEcKC<8;D<KF8EK@:@G8K<K?8KK?<J@;<F=8

D<K8CGC8K<=8IK?<I8N8P=IFD8I8;@8KFINFLC;=<<C N8IDK?<K<DG<I8KLI<_

[ *B8PK?8KN8JEcK@K 8E$KIPKFM<I@=PN?<K?<IK?<;@==LJ@FE<HL8K@FE?FC;JKIL<F=K?@JD<K8CGC8K<8K8CC $J?<8K flowing K?<N8P@KLJL8CCP;F<JFI@JJFD<K?@E><CJ<

>F@E>FE[ $:FLC;?FC;8D8K:?KFK?<GC8K<8E;KIPKFD<8JLI<?FN

?<8KJGI<8;JFM<IK@D<_

+8><b4FLI.KI<E>K?8J8-8K@FE8C@JKc +8><b#@E;J@>?K<M8CL<J.:@<E:<c

%1+,*!'-+ &+/*+,'%1+,*!'-+)-+,!'&+

$= N< 8I< not JKI@:K 89FLK `? D8P9< 9<:8LJ< F= ?<8K :FE;L:eK@FEa 9<@E> 8 =8B< <OGC8E8K@FE K?< JKL;<EK N@CC M<IP GIF989CP ><KJKL:B FE JFD< N8B8C@O<JeG8JJNFI; This happens by default, it hap-

pened to the whole human species for thousands of years.

-++!&,,* 6+(++/'*

15. Science as Attire

.D8CC<IJKFID7Prerequisites: !8B<

OGC8E8K@FEJ <C@<= J KK@I<

/?< GI<M@<N =FI K?< X-Men DFM@< ?8J 8 MF@:<eFM `$E <M<IP ?LD8E 9<@E>_ K?<I< @JK?< ><E<K@: :F;<_ =FIDLK8K@FEa GG8I<EKCP

PFL :8E 8:HL@I< 8CC JFIKJ F= E<8K 89@C@K@<J 9P DLK8K@FE /?< DLK8EK.KFID=FI<O8DGC<?8JK?<89@C@KPKFK?IFNC@>?KE@E>9FCKJ

$ 9<> PFL ;<8I I<8;@:8C D8:?@E<IP E<:e<JJ8IP KF ><E<I8K< <C<:KI@:@KP K?< 9@FCF>@:8C 8;8GK8K@FEJ E<:<JJ8IP KF 8MF@; 9<@E> ?8ID<; 9P <C<:KI@:@KP 8E; K?< :F>E@K@M< :@I:L@KIP I<eHL@I<; =FI =@E<CP KLE<; :FEKIFC F= C@>?KE@E> 9FCKJ $= N< 8:KL8CCP F9J<IM<; 8EP FI>8E@JD 8:HL@I@E> K?<J< 89@C@K@<J in one generation, 8JK?< I<JLCK F= mutation, @K NFLC; FLKI@>?K =8CJ@=P K?< E<Fe8IN@E@8EDF;<C F= E8KLI8C J<C<:K@FE $K NFLC; 9< NFIJ< K?8E =@E;@E> I899@K

=FJJ@CJ @E K?< GI<e8D9I@8E $= <MFCLK@FE8IP K?<FIP :FLC; actuallyJKI<K:? KF :FM 8E;

N<8CCBEFNN?8KK?8KNFLC;@DGCP

/?< X-Men :FD@:J LJ< K<IDJ C@B< `<MFCLK@FEa `DLK8K@FEa 8E;`><E<K@: :F;<a GLI<CP KF GC8:< K?<DJ<CM<J @E N?8K K? ?FN D8EP G<FGC< <JG<:@8CCP @E K?< D<;@8 LE;<IJK8E; J:@<E:<only 8J8C@K<I8IP><EI<

$ <E:FLEKP G<ID@KJ 8E; GIF?@9@KJ/?<PcCC K8CB 89FLK `K?< E<OK JK<G @E K?< <MFCLK@FE F= ?LD8E@KPa 8J@= E8KLI8C J<C<:K@FE >FK ?<I< 9P =FCCFN@E> 8 GC8E *I <M<E NFIJ<K?<PcCC K8CB 89FLK JFD<K?@E> :FDGC<K<CP FLKJ@;< K?< ;FD8@E F= <MFe

http://lesswrong.com/lw/ir/science_as_attire/ +8><b!8B<OGC8E8K@FEJc +8><b<C@<=8JKK@I<c

+8><b4FLI.KI<E>K?8J8-8K@FE8C@JKc +8><b+IF=<JJ@E>8E;?<<I@E>c

CLK@FE8IP 9@FCF>P C@B< 8E @DGIFM<; ;<J@>E =FI :FDGLK FI ?LD8EJ LGCF8;@E> K?<DJ<CM<J @EKF :FDeGLK<IJ 8E; K?<PcCC :8CC that `<MFCLK@FEa $= <MFCLK@FE8IP 9@FCF>P

:FLC;:FM<IK?8K@K:FLC;:FM<I8EPK?@E>+IF989CP 8E 8:KL8C D8AFI@KP F= K?< G<FGC< N?F believe in <MFCLe

K@FE LJ< K?< G?I8J< `9<:8LJ< F= <MFCLK@FEa 9<:8LJ< K? 8 C89 :F8K $= K?< J:@<EK@=@: @Ee:IFN; @EJK<8; LJ<; K?< G?I8J<`9<:8LJ< F= @EK<CC@><EK ;<J@>Ea K? `9<:8LJ< F= <MFCLK@FEa @EJK<8; F= `9<:8LJ< F= @EK<CC@><EK ;<J@>Ea ;F<J EFK for them, GIF?@9@K .KFID $KJ FECP GLIeGFJ<=FIK?<D@JKF@;<EK@=PN@K?8KI@9<

$ <E:FLEK KF <EK<IK8@E K?< EFK@FEF= ;LD9<IeK?8Ee?LD8E IK@=@:@8C $EK<CC@><E:< FI <M<E D@C;CP JD8IK<IeK?8Ee?LD8E IK@=@:@8C $EK<CC@><E:< $EKIF;L:< K?< EFK@FEF= JKIFE>CP JLG<I?LD8E IK@=@:@8C $EK<CC@><E:< 8E; K?<PcCC JL;;<ECP ;<:@;< @KcJ `GJ<L;FJ:@<E:<` $KcJ EFK K?8K K?<E:< N?@:? C<KJ K?<D :8C:LC8K< 8 K?<FI<K@:8C LGG<I9FLE; FE K?< GFNCP JLG<I?LD8E $ KF K?< literary genre F= 8GF:8CPGK@:C@K<I8KLI< N?<I<8J 8E $ ILEE@E> 8 JD8CC :FIGFI8K@FE 8JJF:@8K<J KFK?< C@K<I8IP ><EI< F= Wired D8>8Q@E< /? =IFD

N@K?@E 8 DF;<C F= :F>E@K@FE /? :I@K@HL<J :FEJ@JK GLI<CP F= comparisons to apocalyptic literature I8K?<IK?8E J8P BEFNE C8NJ N?@:? GIF?@9@K JL:? 8E FLK:FD< /?<EI< FI @Ee>IFLG KF 9<CFE> KF/?< 8KK@I< ;F<JEcK CFFB KF K?<D C@B< 8 C89 :F8K K?@J @JEcK K?< =FFKe

98CCK<8DK?<PcI< :?<<I@E> =FI$J K?<I< 8EPK?@E> @E J:@<E:< K?8K PFL 8I< proud F= 9<C@<M@E> 8E;

P<K PFL ;F EFK LJ< K?< 9<C@<= GIF=<JJ@FE8CCP 4FL ?8; 9<JK 8JB PFLIeJ<C= N?@:? =LKLI< <OG<I@<E:<J PFLI 9<C@<= prohibits =IFD ?8GG<E@E> KF PFL /?8K @J K?< JLD F= N?8K PFL ?8M< 8JJ@D@C8K<; 8E; D8;< 8

+8><b!8B<OGC8E8K@FEJc +8><b<C@<=8JKK@I<c http://lesswrong.com/lw/io/is_molecular_nanotechnology_scientific/

+8><b<C@<=8JKK@I<c +8><b+IF=<JJ@E>8E;?<<I@E>c

+!&+,,!*

16. Fake Causality

Followup to !8B< OGC8E8K@FEJ "L<JJ@E> K?< /<8:?<IcJ +8JJe

NFI;

+?CF>@JKFE N8J K?< :<EKLIPcJ 8EJNE@K< NFF; 8E; C<K @K 9LIE 2?8K @JK?< FI8E><Pe9I@>?K `=@I<a JKL== 2?P ;F<J K?< NFF; KI8EJ=FID @EKF8J? /F 9FK? HL<JK@FEJ K?< K?e:<EKLIP :?<D@JKJ 8EJN<I<;`G?CF>@JKFEa

_8E;K?8KN8J@KPFLJ<<K?8KN8JK?<@I8EJN@JKFEa

+?CF>@JKFE <J:8G<; =IFD 9LIE@E> JL9JK8E:<J 8J M@J@9C< =@I< J

K?< G?CF>@JKFE <J:8G<; K?< 9LIE@E> JL9JK8E:<J CFJK G?CF>@JKFE 8E;JF 9<:8D< 8J? K?< `KIL< D8K<I@8Ca !C8D<J @E <E:CFJ<; :FEK8@E<IJ

N<EK FLK 9<:8LJ< K?< 8@I 9<:8D< J8KLI8K<; N@K? G?CF>@JKFE 8E; JF:FLC; EFK ?FC; 8EP DFI< ?8I:F8C C<=K C@KKC< I<J@;L< LGFE 9LIE@E> 9<:8LJ<@KN8JE<8ICPGLI<G?CF>@JKFE

*= :FLIJ< FE< ;@;EcK LJ< G?CF>@JKFE K?<FIP KF predict K?< FLKe:FD< F= 8 :?<D@:8C KI8EJ=FID8K@FE 4FL CFFB<; 8K K?< I<JLCK =@IJKK?<E PFL LJ<; G?CF>@JKFE K?<FIP KF explain @K $KcJ EFK K?8K G?CFe

>@JKFE K?<FI@JKJ GI<;@:K<; 8 =C8D< NFLC; <OK@E>L@J? @E 8 :CFJ<;:FEK8@EF FLK8E; K?<E J8@; `/?< 8@I DLJK ?8M< 9<:FD< J8KLI8K<; N@K? G?CFe

>@JKFEa 4FL :FLC;EcK <M<E LJ< G?CF>@JKFE K?<FIP KF J8P N?8K PFLFL>?K not KFJ<<@K:FLC;<OGC8@E<M<IPK?@E>

/?@J N8J 8E <8IC@< F= J:@<E:< !FI 8 CFE> K@D< EF FE< I<8Ce@Q<; K?<I< N8J 8 GIF9C<D !8B< <OGC8E8K@FEJ ;FEcK feel =8B< /?8KcJ

N?8KD8B<JK?<D;8E><IFLJ

(F;<IE I<J<8I:? JL>><JKJ K?8K ?LD8EJ K?@EB 89FLK :8LJ< 8E;

<==<:K LJ@E> JFD<K?@E> C@B< K?< ;@I<:K<; 8:P:C@: >I8G?J h"Ji F= 8P<J E<KJ <:8LJ< @K I8@E<; K?< J@;<N8CB @J N<K 9<:8LJ< K?< J@;<e

N8CB@JN<K@K@JJC@GG<IP

j-8@Ekej.@;<N8CBN<Kkej.@;<N8CBJC@GG<IPk

http://lesswrong.com/lw/is/fake_causality/ +8><b!8B<OGC8E8K@FEJc +8><b"L<JJ@E>K?</<8:?<IcJ+8JJNFI;c

+8><b4FLI.KI<E>K?8J8-8K@FE8C@JKc +8><b!8B<OGC8E8K@FEJc

!IFD K?@J N< :8E @E=<IgFI @E 8 8P<J E<K I@>FIFLJCP :8C:LC8K<@E GIF989@C@K@<JgK?8K N?<E K?< J@;<N8CB @J JC@GG<IP @K GIF989CP I8@E<; 9LK @= N< 8CI<8;P BEFN K?8K K?< J@;<N8CB @J N<K C<8IE@E>

K?8K K?< J@;<N8CB @J JC@GG<IP K<CCJ LJ EFK?@E> DFI< 89FLK N?<K??KN?<E@K9LIEJ

j`+?CF>@JKFEakej!@I<?FK8E;9I@>?Kk

$K feels C@B< 8E <OGC8E8K@FE $KcJ represented LJ@E> K?< J8D< :F>eE@K@M< ;8K8 =FID8K LK K?< ?LD8E D@E; ;F<J EFK 8LKFD8K@:8CCP ;<K<:K N?<E 8 :8LJ< ?8J 8E LE:FEJKI8@E@E> 8IIFN KF @KJ <==<:K2FIJ< K?8EBJ KF ?@E;J@>?K 9@8J @K D8P =<<C C@B< K?< :8LJ< :FEe

JKI8@EJ

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17. Semantic Stopsigns

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18. Mysterious Answers to MysteriousQuestions

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;<E:<:8D<BEF:B@E>/?< .<:I<K F= '@=< N8J infinitely beyond the reach of science! )FK ALJK

8 little 9<PFE; D@E; PFL 9LK infinitely 9<PFE; 'FI; &<CM@E JLI< ;@; ><K8KI<D<E;FLJ<DFK@FE8CB@:BFLKF= not knowing something.

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1@K8C@JD J?8I<; N@K? G?CF>@JKFE K?< <IIFI F= encapsulating the mystery as a substance. !@I< N8J DPJK<I@FLJ 8E; K?< G?CF>@JKFE K?<FIP

+8><b!8B<OGC8E8K@FEJc +8><b!8B<8LJ8C@KPc +8><b.<D8EK@:.KFGJ@>EJc +8><b!8B<8LJ8C@KPc

http://lesswrong.com/lw/h8/tsuyoku_naritai_i_want_to_become_stronger/ http://yudkowsky.net/virtues/

%1+,*!'-+ &+/*+,'%1+,*!'-+)-+,!'&+

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/?<I<=FI< $ :8CC K?<FI@<J JL:? 8J M@K8C@JD mysterious answers to mysterious questions

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+8><b!F:LJ4FLI0E:<IK8@EKPc +8><b.<D8EK@:.KFGJ@>EJc

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G?<EFD<E8[ !FLIK? even after the answer is given, the phenomenon is still a mystery 8E;GFJJ<JJ<JK?<J8D<HL8C@KPF=NFE;<I=LC@E<OGC@:89@C@KPK?8K@K?8;8KK?<JK8IK


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19. The Futility of Emergence

Prerequisites: <C@<= @E <C@<= !8B< OGC8E8K@FEJ !8B< 8LJ8Ce

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N?@:?$;<<D8E8CF>FLJCP=C8N<;

$ E8D< emergence FI emergent phenomena gLJL8CCP ;<=@E<; 8J K?<JKL;P F= JPJK<DJ N?FJ< ?@>?eC<M<C 9<?8M@FIJ 8I@J< FI `<D<a =IFDK?< @EK<I8:K@FE F= D8EP CFNeC<M<C <C<D<EKJ h2@B@G<;@8 `/?<

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http://lesswrong.com/lw/iv/the_futility_of_emergence/ +8><b<C@<=@E<C@<=c +8><b!8B<OGC8E8K@FEJc +8><b!8B<8LJ8C@KPc +8><b(PJK<I@FLJEJN<IJKF(PJK<I@FLJ,L<JK@FEJc +8><b!8B<8LJ8C@KPc +8><b(PJK<I@FLJEJN<IJKF(PJK<I@FLJ,L<JK@FEJc +8><b#@E;J@>?K<M8CL<J.:@<E:<c

+8><b#@E;J@>?K9@8Jc http://en.wikipedia.org/wiki/Emergence

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[ Even better: :FCFEP@JD8;<F=8EKJ2<:8EJL::<JJ=LCCP GI<;@:KJFD<8JG<:KJF=:FCFEP9<?8M@FILJ@E>DF;<CJK?8K@E:CL;<FECP@E;@M@;L8C8EKJN@K?FLK8EP>CF98C:FCFEP

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,-,!$!,1'%*&

20. Say Not “Complexity”

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E;$J8@;`FEcKJ8Pbcomplexity’.a

(8I:<CCFJ8@;`2?PEFKa

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$ J8@; `@; PFL I<8; /<:?E@:8C OGC8E8K@FE F= /<:?E@:8C OeGC8E8K@FEa

http://lesswrong.com/lw/ix/say_not_complexity/ http://yudkowsky.net/bayes/technical.html

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+1&',4'%($0!,15

21. Positive Bias: Look Into the Dark

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22. My Wild and Reckless Youth

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EJN<I8E;J8@;KFDPJ<C= No way am I falling for that again.

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/?<8IK?9<:8D<FC;<IF=8JL;;<E

/F DP =FID<b!8@C@E>KF'<8IE=IFD#@JKFIPc http://en.wikipedia.org/wiki/Availability_heuristic

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25. Explain/Worship/Ignore?

Followup to .<D8EK@: .KFGJ@>EJ (PJK<I@FLJ EJN<IJ KF (PJK<e

I@FLJ,L<JK@FEJ

J FLI KI@9< N8E;<IJ K?IFL>? K?< >I8JJC8E;J J<8I:?@E> =FI =IL@KKI<<J 8E; GI E<M<I F::LII<; KF?@D 9<=FI< 8E; K?<E J8PJ `!IFD K@D< KF K@D< K?< JBP JG@I@KJ 98Ke

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)FN 8J PFL 8I< 9FLE; KF EFK@:< =IFD K?@J JKFIP <8:? K@D< PFLJ<C<:K OGC8@E K?< 9<JKe:8J< J:<E8I@F @J K?8K PFL ><K 8E <OGC8E8K@FEJL:? 8J `JBP JG@I@KJa LK K?<E K?@J <OGC8E8K@FE @KJ<C= @J JL9A<:K KFK?< J8D< ;@C<DD8gOGC8@E 2FIJ?@G FI $>EFI< 8:? K@D< PFL?@K OGC8@E J:@<E:< >I@E;J =FI 8 N?@C< I<KLIEJ 8E <OGC8E8K@FE 8E;

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http://lesswrong.com/lw/j2/explainworshipignore/

+8><b.<D8EK@:.KFGJ@>EJc +8><b(PJK<I@FLJEJN<IJKF(PJK<I@FLJ,L<JK@FEJc

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26. “Science” as Curiosity-Stopper

Followup to .<D8EK@: .KFGJ@>EJ (PJK<I@FLJ EJN<IJ KF (PJK<e

I@FLJ,L<JK@FEJ .8P)FKbFDGC<O@KPc

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LK EFN JLGGFJ< @EJK<8; K?8K $ ;FEcK >F FE K<C<M@J@FE $ ;F EFK N@J? KF J?8I< K?< GFN?K JF K?8K$ :8E I<8; 8 9FFB FE K?< KI8@EgN@K?FLK 8EPFE< 9<:FD@E> :LI@FLJ$JK?<I<8JG<CCK?8KJKFGJ:LI@FJ@KP

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http://lesswrong.com/lw/j3/science_as_curiositystopper/ +8><b.<D8EK@:.KFGJ@>EJc +8><b(PJK<I@FLJEJN<IJKF(PJK<I@FLJ,L<JK@FEJc +8><b.8P)FK`FDGC<O@KPac +8><b!8B<OGC8E8K@FEJc +8><b.<D8EK@:.KFGJ@>EJc

+8><b"L<JJ@E>K?</<8:?<IcJ+8JJNFI;c +8><b"L<JJ@E>K?</<8:?<IcJ+8JJNFI;c

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=<NG<FGC<BEFN?FNKFG<I=FIDi$= PFL K?FL>?K K?< C@>?K 9LC9 N8J scientifically inexplicable, @K

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`*?a PFL J8P `@E K?8K :8J< E<M<I D@E;a 8E; N8CB FE KF K?<B@K:?<E

http://lesswrong.com/lw/kr/an_alien_god/ http://godescalc.wordpress.com/2012/06/24/overlooked-elephant/

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27. Applause Lights

Followup to .<D8EK@: .KFGJ@>EJ 2< FEcK -<8CCP 28EK 4FLI

+8IK@:@G8K@FE

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/?<=@IJKJ:<E8I@FJFLE;JC@B<8E<;@KFI@8C@E-<8JFED8>8Q@E<8E;K?<J<:FE;JFLE;JC@B<8#FCCPNFF;DFM@<GCFK

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http://lesswrong.com/lw/jb/applause_lights/

+8><b.<D8EK@:.KFGJ@>EJc http://lesswrong.com/lw/ja/we_dont_really_want_your_participation/

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http://www.time.com/time/magazine/article/0,9171,954853,00.html

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28. Truly Part Of You

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http://lesswrong.com/lw/la/truly_part_of_you/ +8><b"L<JJ@E>K?</<8:?<IcJ+8JJNFI;c http://lesswrong.com/lw/l9/artificial_addition/

http://ontolog.cim3.net/forum/ontolog-forum/2006-04/pdfb9P8wB8aYh.pdf +8><b"L<JJ@E>K?</<8:?<IcJ+8JJNFI;c

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29. Chaotic Inversion

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http://lesswrong.com/lw/wb/chaotic_inversion/

http://lesswrong.com/lw/un/on_doing_the_impossible/ +8><b(@E;+IFA<:K@FE!8CC8:Pc

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1. The Parable of the Dagger

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`@K?<IK?@J9FO:FEK8@EJ>FC;8E;K?<9FON@K?8=8CJ<

@EJ:I@GK@FE:FEK8@EJ8E8E>IP=IF>FIK?@J9FO:FEK8@EJ8E8E>IP=IF>8E;K?<9FON@K?8KIL<@EJ:I@GK@FE:FEK8@EJ

>FC;a

E; K?< A<JK `*E< 9FO :FEK8@EJ 8E 8E>IP =IF> K?< FK?FC; 8E; FE< 8E; FECP FE< F= K?< @EJ:I@GK@FEJ@JKIL<a

/?< B@E> FG<E<; K?< NIFE> 9FO 8E; N8J J8M8><; 9P 8E 8E>IP

=IF>4FL J<<a K?< A<JKFC;/?<E K?< FK?IP =IF> N?@C< K?< 9FO N@K? 8 KIL< @EJ:I@GK@FE NFLC; :FEK8@E >FC; N?@:? NFLC; D8B< K?< J<:FE;JK8K<D<EK KIL< 8J N<CC )FN ?PGFK?<J@Q< K?8K K?< =@IJK @EJ:I@GK@FE@J =8CJ< 8E; K?8K K?< =@IJK 9FO :FEK8@EJ >FC; /?<E K?< J<:FE; @EeJ:I@GK@FENFLC;9<ga

/?<B@E>FI;<I<;K?<A<JK<IK?IFNE@EK?<;LE><FEJ

;8P C8K?K 9<=FI< K?< B@E> @E :?8@EJ 8E;J?FNEKNF9FO<J

`*E< 9FO :FEK8@EJ 8 B<Pa J8@; K?< B@E> `KF LECF:B PFLI :?8@EJ8E; @= PFL =@E; K?< B><I=FIPFLI?<8IK@=PFL=8@Ca

E;K?<=@IJK9FON8J@EJ:I@9<;

http://lesswrong.com/lw/ne/the_parable_of_the_dagger/

`@K?<I9FK?@EJ:I@GK@FEJ8I<KIL<FI9FK?@EJ:I@GK@FEJ8I<=8CJ<a

E;K?<J<:FE;9FON8J@EJ:I@9<;

`/?@J9FO:FEK8@EJK?<B<Pa

/?< A<JK8@E K?< J<:FE; @EJ:I@GK@FEDLJK 9< KIL< .F K?< J<:FE; 9FO DLJK :FEK8@E K?< B@:8CCP:FEK8@EK?<B<Pa/?<A<JK<IFG<E<;K?<J<:FE;9FO8E;=FLE;8;8>>><; 8N8P `$KcJCF>@:8CCP@DGFJJ@9C<a

`$K @J <EK@I<CP GFJJ@9C<a I<GC@<; K?< B@E> `$ D<I<CP NIFK< K?FJ<@EJ:I@GK@FEJ FE KNF 9FO<J 8E; K?<E $ GLK K?< ;8>><I @E K?< J<:FE;FE<a

(Adapted from Raymond Smullyan.)

-%&6+-!,'/'*+

2. The Parable of Hemlock

Followup to /?<+8I89C<F=K?<8>>?KFB@CCJFN@J<8E;>FF;8D8Ea`)Fa I<GC@<; 8EFK?<I 9PJK8E;<I 8 JKL;<EK F= G?@CFJFG?P `8CC

D<E 8I< DFIK8C 8E; .F:I8K<J @J 8 D8E 8E; @= 8 DFIK8C ;I@EB ?<DeCF:BJLI<CP?<;@<Ja

`2<CCa J8@; K?< FECFFB<I `N?8K @= @K ?8GG<EJ K?8K .F:I8K<J isn’t DFIK8Ca

`)FEJ<EJ<a I<GC@<; K?< JKL;<EK 8 C@KKC< J?8IGCP `8CC D<E 8I< DFIeK8C by definition @K @J G8IK F= N?8K N< D<8E 9P K?< NFI; bD8Ec CCD<E 8I< DFIK8C .F:I8K<J @J 8 D8E K?<I<=FI< .F:I8K<J @J DFIK8C $K@JEFKD<I<CP8>L<JJ9LK8 logical certainty.a

`$ JLGGFJ< K?8KcJ I@>?K_a J8@; K?< FECFFBa

`4<J ?< J?FLC; 9< B<<C@E> FM<I 8EP D@ELK< EFNa J8@; K?< JKLe;<EK

And they waited, and they waited, and they waited…`.F:I8K<J8GG<8IJEFKKF9<DFIK8CaJ8@;K?<FECFFB<I`/?<E .F:I8K<J DLJK EFK 9< 8 D8Ea I<GC@<; K?< JKL;<EK `CC

D<E 8I< DFIK8C .F:I8K<J @J EFK DFIK8C K?<I<=FI< .F:I8K<J @J EFK 8 D8E E;K?8K@JEFKD<I<CP8>L<JJ9LK8 logical certainty.a

/?< =LE;8D<EK8C GIF9C<D N@K? 8I>L@E> K?8K K?@E>J 8I< KIL< `9P ;<=@E@K@FEa @J K?8K PFL :8EcK D8B< I<8C@KP >F 8 ;@==<I<EK N8P 9P :?FFJ@E>8;@==<I<EK;<=@E@K@FE

4FL :FLC; I<8JFE G<I?8GJ 8J =FCCFNJ `CC K?@E>J $ ?8M< F9eJ<IM<; N?@:? N<8I :CFK?@E> JG<8B C8E>L8>< 8E; LJ< KFFCJ ?8M< 8CJFJ?8I<; :<IK8@E FK? 8@I 8E;GLDG@E> I<; 9CFF; /?< C8JK K?@IKP b?LD8EJc 9<CFE>@E> KF K?@J :CLJe

http://lesswrong.com/lw/nf/the_parable_of_hemlock/

+8><b/?<+8I89C<F=K?<8>><Ic http://machall.com/view.php?date=2003-04-21

K .F:I8K<J N<8IJ 8 KF>8 JG<8BJ =CL<EK 8E:@<EK "I<<B 8E;;I8EB ?<DCF:B =IFD 8 :LG .F $ GI<;@:K K?8K .F:I8K<J N@CC B<<C FM<I

@EK?<E<OK=@M<D@ELK<JaLK K?8K NFLC; 9< D<I< guessing. $K NFLC;EcK 9< PcBEFN 89JFe

CLK<CP 8E; <K<IE8CCP :<IK8@E /?< "I< I<AF@E; 4FL ?8M< D@JLE;<IJKFF; K?< D<8E@E> F= `CC ?LeD8EJ 8I< DFIK8Ca K?<K?@:8CCP M8C@; KILK? 89JFCLK<CP LEHL<JK@FEe89C< E; @= .F:I8K<J @J ?LD8E ?< must 9< DFIK8C @K @J 8 CF>@:8C;<;L:K@FE8J:<IK8@E8J:<IK8@E:8E9<

LK K?<E N< :8E E<MFF; KF F9J<IM< K?8K .F:I8K<J JG<8BJ =CL<EK "I<<B FI K?8K.F:I8K<J ?8J I<; 9CFF; FI <M<E K?8K .F:I8K<J ?8J ?LD8E )

)FE< F= K?<J< :?8I8:K<I@JK@:J 8I< logically equivalent KF DFIK8C@KP4FL ?8M< KF see him die 9<=FI< PFL :8E :FE:CL;< K?8K ?< N8J ?LD8E

hE; <M<E K?<E @KcJ EFK @E=@E@K<CP :<IK8@E 2?8K @= .F:I8K<JI@J<J =IFD K?< >I8M< 8 E@>?K 8=KE<; LG =FI :IPFE@:J $= DFIK8C@KP @J;<=@E<; KF D<8E =@E@K< C@=<JG8E K?<E PFL :8E E<M<I I<8CCP know @= JFD<FE< N8J ?LD8E LEK@C PFLcM< F9J<IM<; KF K?< <E; F= <K<IE@eKPgALJK KF D8B< JLI< K?_i

/?< GIF9C<D N@K? JPCCF>@JDJ @J K?8K K?<PcI< always M8C@; `CC?LD8EJ 8I< DFIK8C .F:I8K<J @J ?LD8E K?<I<=FI< .F:I8K<J @J DFIK8Ca@Jg@= PFL KI<8K @K 8J 8 CF>@:8C JPCCF>@JDgCF>@:8CCP M8C@; N@K?@E FLIFNE LE@M<IJ< $KcJ 8CJF CF>@:8CCP M8C@; N@K?@E E<@>?9FI@E> M<I<KK9I8E:?<J @E N?@:? ;L< KF 8 JC@>?KCP ;@==<I<EK <MFCM<; 9@F:?<D@JKIP

+8><b9JFCLK<LK?FI@KPc +8><b$E=@E@K<<IK8@EKPc

-%&6+-!,'/'*+

?<DCF:B @J 8 ;<C@:@FLJ KI<8K I8K?@:8CCP M8C@; <M<E @E LE@M<IJ<J N?<I< .F:I8K<J E<M 8 ?PGFK?<J@J @J <Me@;<E:< N?@:? N< 8I< DFI< C@B<CP KF J<< @= K?< ?PGFK?<J@J @J KIL< K?8E@= @K @J =8CJ< *9J<IM@E> K?8K 8 JPCCF>@JD @J CF>@:8CCP M8C@; :8E E<M<I9< <M@;<E:< =8MFI@E> 8EP <DG@I@:8C GIFGFJ@K@FE 9<:8LJ< K?< JPCCFe

>@JDN@CC9<CF>@:8CCPM8C@;N?<K?<IK?8KGIFGFJ@K@FE@JKIL<FI=8CJ<

.PCCF>@JDJ 8I< M8C@; @E 8CC GFJJ@9C< NFIC;J 8E; K?<I<=FI< F9J<IMe@E> K?<@I M8C@;@KP E<M 89FLK which GFJJ@9C< NFIC;

N<8:KL8CCPC@M<@E

/?@J ;F<JEcK D<8E K?8K CF>@: @J LJ<C<JJgALJK K?8K CF>@: :8E FECP K<CC LJ K?8K N?@:? in some sense, N< 8CI<8;P BEFN LK N< ;F EFK 8Ce

N8PJ 9<C@<M< N?8K N< BEFN $J K?< ELD9@: KF=@E;FLK

.@D@C8ICP @= $ =FID K?< LE:<IK8@E <DG@I@:8C ><E<I8C@Q8K@FE `#LeD8EJ 8I< MLCE<I89C< KF ?<DCF:Ba 8E; K?< LE:<IK8@E <DG@I@:8C >L<JJ

`.F:I8K<J @J ?LD8Ea CF>@: :8E K<CC D< K?8K DP GI<M@FLJ >L<JJ<J 8I<GI<;@:K@E>K?8K.F:I8K<JN@CC9<MLCE<I89C<KF?<DCF:B

$KcJ 9<<E JL>><JK<; K?8K N< :8E M@<N CF>@:8C I<8JFE@E> 8J I<JFCMe@E> FLI LE:<IK8@EKP 89FLK @DGFJJ@9C< GFJJ@9C< NFIC;Jg<C@D@E8K@E> GIF989@C@KP D8JJ @E CF>@:8CCP @DGFJJ@9C< NFIC;J N?@:? N< ;@; EFKBEFN KF 9< CF>@:8CCP @DGFJJ@9C< $E K?@J J<EJ< CF>@:8C 8I>LD<EK :8E9< KI<8K<;8JF9J<IM8K@FE

LK N?<E PFL K8CB 89FLK 8E <DG@I@:8C GI<;@:K@FE C@B< `.F:I8K<J

@J >F@E> KF B<<C FMa FI `.F:I8K<J @J >F@E> KF ;F=@=KP ALDG@E> A8:BJ 8E; K?<E :FDG<K< @E K?< *CPDG@:J E<OK P<8IaK?8K@J8D8KK<IF=GFJJ@9C<NFIC;JEFK@DGFJJ@9C<GFJJ@9C<NFIC;J

'F>@: :8E K<CC LJ N?@:? ?PGFK?<J<J D8K:? LG KF N?@:? F9J<Ie M8K@FEJ 8E; @K :8E K<CC LJ N?8K K?<J< ?PGFK?<J<J GI<;@:K =FI K?<=LKLI<g@K :8E 9I@E> FC; F9J<IM8K@FEJ 8E; GI<M@FLJ >L<JJ<J KF 9<8IFE 8 E<N GIF9C<D LK CF>@: E<M EFNa 'F>@: E<M<bE$EKL@K@M<OGC8E8K@FEF=8P<J/?<FI<Dc +8><b#FNKFFEM@E:<(</?8Kc

,(*$'%$'#

@E8K@FE>F<@K?<IN8P

%LJKI<D<D9<IK?<'@K8EP>8@EJK'F>@:

'F>@:JK8PJKIL<N?<I<M<IPFLD8P>F.FCF>@:E<M<IK<CCJPFLN?<I<PFLC@M<

-%&6+-!,'/'*+

3. Words as Hidden Inferences

Followup to /?<+8I89C<F=#<DCF:B

.LGGFJ< $ =@E; 8 98II<C J<8C<; 8K K?< KFG 9LK N@K? 8 ?FC< C8I><<EFL>? =FI 8 ?8E; $ I<8:? @E 8E; =<<C 8 JD8CC :LIM<; F9A<:K $GLCC K?< F9A<:K FLK 8E; @KcJ 9CL<g8 9CL@J? <>> )<OK $ I<8:? @E 8E;=<<C JFD<K?@E> ?8I; 8E; =C8K N@K? <;><JgN?@:? N?<E $ <OKI8:K @KGIFM<J KF 9< 8 I<; :L9< $ GLCC FLK <>>J 8E; :L9<J 8E; <M<IP <>>@J9CL<8E;<M<IP:L9<@JI<;

)FN $ I<8:? @E 8E; $ =<<C 8EFK?>eJ?8G<; F9A<:K <=FI< $GLCC@KFLK8E;CFFB$?8M<KF>L<JJ 2?8KN@CC@KCFFBC@B<

/?< <M@;<E:< ;F<JEcK GIFM< K?8K <M<IP <>> @E K?< 98II<C @J 9CL<8E; <M<IP :L9< @J I<; /?< <M@;<E:< ;F<JEcK <M<E 8I>L< K?@J 8CC K?8KJKIFE>CP @J EFK 8 C8I>< J8DGC< J@Q< )FE<K?<C<JJ $cCC >L<JJ K?8KK?@J <>>eJ?8G<; F9A<:K @J 9CL<gFI 8J 8 ILEE<IeLG >L<JJ I<; $= $

>L<JJ 8EPK?@E> <CJ< K?<I<cJ 8J D8EP GFJJ@9@C@K@<J 8J ;@JK@E>L@J?89C<:FCFIJg8E; =FI K?8K D8KK> ?8J KF 9< 8 J@E>C<J?8;< (8P9<@K?8J8G@:KLI<F=8?FIJ<G8@EK<;FE

.F $ J8P `9CL<a N@K? 8 ;LK@=LC G8K@E8 F= ?LD@C@KP !FI $ 8D8 JFG?@JK@:8K<; I8K@FE8C@JKeKPG< G<IJFE 8E; $ B<<G KI8:B F= DP

8JJLDGK@FEJ 8E; ;<G<E;<E:@<Jg$ >L<JJ 9LK $cD 8N8I< K?8K $cD >L<JJ@E>_I@>?K

LK N?<E 8 C8I>< P<CCFN JKI@G<; =<C@E<eJ?8G<; F9A<:K C<8GJ FLK 8KD< =IFD K?< J?8;FNJ $ K?@EB `4@B<J K@><Ia )FK `#D_ F9eA<:KJ N@K? K?< GIFG<IK@<J F= C8I><E<JJ P<CCFNE<JJ JKI@G<;E<JJ 8E;=<C@E< J?8G< ?8M< GI<M@FLJCP F=K<E GFJJ<JJ<; K?< GIFG<IK@<J b?LEe

>IPc 8E; b;8E><IFLJc 8E; K?LJ 8CK?FL>? @K @J EFK CF>@:8CCP E<:<JJ8IP@K D8P 9< 8E <DG@I@:8CCP >FF; >L<JJ K?8K aaauuughhhh -0)#

-0)#"0'+a/?< ?LD8E 9I8@E =FI JFD< F;; I<8JFE J<<DJ KF ?8M< 9<<E8;8GK<; KF D8B< K?@J @E=<I<E:< HL@:BCP 8LKFD8K@:8CCP 8E; N@K?FLKB<<G@E><OGC@:@KKI8:BF=@KJ8JJLDGK@FEJ

E; @= $ E8D< K?< <>>eJ?8G<; F9A<:KJ `9C<>>Ja h=FI 9CL< <>>Ji8E; K?< I<; :L9<J `IL9<Ja K?<E N?<E $ I<8:? @E 8E; =<<C 8EFK?<I<>>eJ?8G<; F9A<:K $ D8P K?@EB Oh, it’s a blegg, I8K?8CCK?8KGIF9C<DeF=e@E;L:K@FEJKL==

http://lesswrong.com/lw/ng/words_as_hidden_inferences/ +8><b/?<+8I89C<F=#<DCF:Bc

$K @J 8 :FDDFE D@J:FE:<GK@FE K?8K PFL :8E ;<=@E< 8 NFI; 8EP N8PPFLC@B<

/?@J NFLC; 9< KIL< if K?< 9I8@E KI<8K<; NFI;J 8J GLI<CP CF>@:8C

:FEJKIL:KJ I@JKFK<C@8E :C8JJ<J 8E; PFL E<MF<J FE 89FLK @KJ NFIB F= :8K<>FI@Q8K@FE N?<K?<IFI EFK N< :FEJ:@FLJCP 8GGIFM< `CC ?LD8EJ 8I< DFIK8C .F:I8K<J@J 8 ?LD8E K?<I<=FI< .F:I8K<J @J DFIK8CagK?LJ JG8B< K?< 8E:@<EK"I<@:8C ;<=e@E@K@FE F= `?LD8Ea PFL :8EcK CF>@:8CCP :C8JJ@=P .F:I8K<J 8J ?LD8ELEK@C PFL F9J<IM< ?@D KF 9< DFIK8C LKgK?@J @J K?< GIF9eC<DgI@JKFKC< BE<N G<I=<:KCP N<CC K?8K .F:I8K<J N8J 8 ?LD8E

I@JKFKC<cJ 9I8@E GC8:<; .F:I8K<J @E K?< `?LD8Ea :8K<>FIP 8J <==@e:@<EKCP 8J PFLI FNE 9I8@E :8K<>FI@Q<J K@><IJ 8GGC<J 8E; <M<IPK?@E> <CJ< @E @KJ <EM@IFED<EK .N@=KCP J@C<EKCP 8E; N@K?FLK :FEJ:@FLJ 8GeGIFM8C

I@JKFKC< C8@; ;FNE ILC<J LE; K?8K C@M@E> G<FGC< N<I< ?LeD8EJ 8E; K?<I<=FI< DFIK8C K?L@J?@E> GIFG<IK@<J JL:?

8J ?LD8E =8:<J 8E; ?LD8E 9F;@<J 8E; K?<@I 9I8@EJ D8;< K?< C<8GKF@E=<II<;GIFG<IK@<JJL:?8JDFIK8C@KP

(@JLE;<IJK8E;@E> K?< NFIB@E> F= PFLI FNE D@E; ;F<J not,K?8EB=LCCP GI<M<EK K?< D@E; =IFD ;F@E> @KJ NFIB *K?<IN@J< I@JeKFK<C@8EJ NFLC; ?8M< JK8IM<; LE89C< KF :FE:CL;< K?8K 8E F9A<:K N8J<;@9C<D<I<CP9<:8LJ<@KCFFB<;8E;=<CKC@B<898E8E8

.F K?< I@JKFK<C@8EJ N<EK FE :C8JJ@=P@E> <EM@IFED<EK8C F9A<:KJFE K?< 98J@J F= G8IK@8C @E=FID8K@FE K?< N8P G<FGC< ?8; 8CN8PJ;FE< .KL;<EKJ F= I@JKFK<C@8E CF>@: N<EK FE K?@EB@E> <O8:KCP K?<J8D< N8P 9LK K?

$= PFL 8JB<; 8E I@JKFK<C@8E G?@CFJFG?IFe:L<JJ FI 8 :<IK8@EKP 8E; K?<b/?<+8I89C<F=#<DCF:Bc +8><b/?<+8I89C<F=#<DCF:Bc

-%&6+-!,'/'*+

K?< J@OK<<EK? :<EKLIP 8K C<8JKi JB K?<D ?FN K?@E8C E8KLI<J 9LK K? /? LEC@B< K?<@I KIL< J<CM<J K?@:8C ;<=@E@K@FEJ N@K? EF<DG@I@:8C :FEJ<HL<E:<J 8E; JF E<@K? 8 NFI; :8E :8LJ< PFLI D@E; KF 8CCF:8K< 8 :8K<>FIP 8E;K?<I<9P KI@>><K PFLI D@E; KF8CCF:8K< KNF :8K<>FI@<J )FK@:< ?FN $ J8@; `PFLa 8E; `PFLI 9I8@Ea8J@=K?<PN<I<;@==<I<EKK?@E>J

(8B@E> <IIFIJ 89FLK K?< @EJ@;< F= PFLI ?<8; ;F<JEcK :?8E>< N?8KcJ K?<I< FK?<IN@J< I@JKFKC< NFLC; ?8M< ;@<; N?<E ?< :FE:CL;e<; K?8K K?< 9I8@E N8J 8E FI>8E =FI :FFC@E> K?< 9CFF; +?@CFJFG?@:8CD@JK8B<J LJL8CCP ;FEcK @EK<I=<I< N@K? 9C@EBeF=e8Ee<P< G<I:<GKL8C @Ee=<I<E:<J

LK G?@CFJFG?@:8C D@JK8B<J :8E J<M<I<CP D<JJ LG K?< ;<C@9<I8K<K?@EB@E> GIF:<JJ<J K?8K N< LJ< KF KIP KF :FII<:K FLI =@IJK @DGI<JeJ@FEJ $= PFL 9<C@<M< K?8K PFL :8E `;<=@E< 8 NFI; 8EP N8P PFL C@B<a

N@K?FLK I<8C@Q@E> K?8K PFLI 9I8@E >F<J FE :8K<>FI@Q@E> N@K?FLK PFLI:FEJ:@FLJ FM<IJ@>?K K?<E PFL NFEcK K8B< K?< <==FIK KF :?FFJ< PFLI;<=@E@K@FEJN@J<CP

+8><b/?<'<EJ/?8K.<<J$KJ!C8NJc http://lesswrong.com/lw/mg/the_twoparty_swindle/

/'*++!&! &*&+

4. Extensions and Intensions

Followup to 2FI;J8J#@;;<E$E=<I<E:<J

`2?8K@JI<;a`-<;@J8:FCFIa`2?8KcJ8:FCFIa`:FCFI@J8GIFG<IKPF=8K?@E>a

LK N?8K @J 8 K?@E> E; N?8KcJ 8 GIFG<IKP .FFE K?< KNF 8I<CFJK @E 8 D8Q< F= NFI;J ;<=@E<; @E FK? KF C<8IE ?@E<J< =IFD 8 ?@E<J<?@E<J<;@:K@FE8IP

CK<IE8K@M<CP @= PFL 8JB<; D< `2?8K @J I<;a $ :FLC; GF@EK KF8 JKFG J@>E K?<E KF JFD<FE< N<8I@E> 8 I<; J?@IK 8E; 8 KI8==@: C@>?KK?8K ?8GG<EJ KF 9< I<; 8E; 9CFF; =IFD N?<I< $ 8::@;<EK8CCP :LKDPJ<C= 8E; 8 I<; 9LJ@E<JJ :8I; 8E; K?<E $ :FLC; :8CC LG 8 :FCFI

N?<<C FE DP :FDGLK? @= PFL BEFN N?8K K?< NFI;`)Fa D<8EJ K?< KILCP JKI@:K NFLC; @EJ@JK K?8K $ GF@EK KF K?< JBP

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LK K?8KcJ ?FN $ I<D<D9 89FLK K?< ;@==<I<E:<9<KN<<E @EK<EJ@FE8C 8E; <OK<EJ@FE8C ;<=@E@K@FE /F >@M< 8E `@EK<EeJ@FE8C ;<=@E@K@FEa @J KF ;<=@E< 8 NFI; FI G?I8J< @E K<IDJ F= FK?@M< 8E `<OK<EJ@FE8C ;<=@E@K@FEa @JKF GF@EK KF <O8DGC<J 8J 8;LCKJ ;F N?<E K<8:?@E> :?@C;I<E /?<GI<:<;@E> J<EK<E:< >@M<J 8E @EK<EJ@FE8C ;<=@E@K@FE F= `<OK<EJ@FE8C;<=@E@K@FEa N?@:? D8B<J @K 8E <OK<EJ@FE8C <O8DGC< F= `@EK<EJ@FE8C;<=@E@K@FEa

http://lesswrong.com/lw/nh/extensions_and_intensions/ +8><b2FI;J8J#@;;<E$E=<I<E:<Jc

http://www.ecs.soton.ac.uk/%7Eharnad/Papers/Harnad/harnad90.sgproblem.html +8><b+FJ@K@M<@8J'FFB$EKFK?<8IBc

$E #FCCPNFF; -8K@FE8C@KP 8E; GFGLC8I :LCKLI< ><E<I8CCP `I8K@FeE8C@JKJa 8I< ;<G@:K<; 8J NFI;eF9J<JJ<; =CF8K@E> @E <E;C<JJ M<I98CJG8:<;@J:FEE<:K<;=IFDI<8C@KP

LK K?< 8:KL8C /I8;@K@FE8C -8K@FE8C@JKJ ?8M< CFE> @EJ@JK<; FED8@EK8@E@E>8K@>?K:FEE<:K@FEKF<OG<I@<E:<

`$=PFLCFFB@EKF8K<OK9FFBF=:?<D@JKIP=FI8;<=@E@K@FEF=C@K?@LDPFLD8P9<KFC;K?8K@K@JK?8K<C<D<EKN?FJ<8KFD@:N<@>?K@JM<IPE<8ICPLK@=K?<8LK?FI?8J8 DFI<CF>@:8CD@E;?<N@CCK<CCPFLK?8K@=PFLJ<8I:?8DFE>D@E<I8CJK?8K8I<M@KI<FLJKI8EJCL:<EK>I<PFI

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0,&+!'&+&! &,&+!'&+

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:FDDLE@:8K< maps to :FE:<GKJ FI @EJKIL:K@FEJ =FI 9L@C;@E> :FEe:<GKJgPFL ;FEcK :FDDLE@:8K< K?< actual :8K<>FI@<J 8J K?? :I<8K@M@KP PFL :8E :FEJKIL:K <O:<GK@FEJ KFK?@J ILC< C@B< `.<EK<E:<J C@<Q K?< K<ID b?LI8>8CFE@c 8J F= !<9 a $cM< ALJK J?FNE PFL K?@J:FE:<GKcJ <EK@I< <OK<EJ@FE LK <O:<GK @E D8K?<D8K@:J ;<=@E@K@FEJ8I<LJL8CCPKI<8JLI<D8GJEFKKI<8JLII8D :FE:<GKJ @EKF JFD<FE< <CJ<cJ9I8@E

M<E N@K?@E K?< I@JKFK<C@8E G8I8;@>D N?<I< N< GI<K<E; K?8KK?< ;<=@E@K@FEJ 8I< K?< 8:KL8C :FE:<GKJ PFL ;FEcK ?8M< simultaneous=I<<;FD F= @EK<EJ@FE 8E; <OK<EJ@FE .LGGFJ< $ ;<=@E< (8IJ 8J `?L>< I<; IF:BP JG?<I< 8IFLE; 8 K<EK? F= 8IK?cJ D8JJ 8E; n=LIK? @E DP <OG<I@<E:< FI @E;<<; K?8K @K D8K:?<J 8EP I<8C K?@E>

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2?<E PFL K8B< @EKF 8::FLEK K?< N8P K?< ?LD8E D@E; 8:KL8CCPGI8>D8K@:8CCP NFIBJ K?< EFK@FE `$ :8E ;<=@E< 8 NFI; 8EP N8P $ C@B<aJFFE 9<:FD<J `$ :8E 9<C@<M< 8EPK?@E> $ N8EK 89FLK 8 =@O<; J<K F= F9A<:KJa FI `$ :8E DFM< 8EP F9A<:K $ N8EK @E FI FLK F= 8 =@O<; D<De9<IJ?@G K<JKa %LJK 8J PFL :8EcK LJL8CCP :FEM :FDGC@:8K<; E<LI8C D<D9<IeJ?@G K<JK PFL :8EcK control K?< :FE:<GKcJ <EK@I< @EK<EJ@FE 9<:8LJ< @KcJ8GGC@<; JL9e;<C@9<I8K<CP /?@J @J N?P 8I>L@E> K?8K 345 @J KIL< `9P

;<=@E@K@FEa @J JF GFGLC8I $= ;<=@E@K@FE :?8E><J 9<?8M<; C@B< K?< <DeG@I@:8C ELCCFGJ K?<PcI< JLGGFJ<; KF 9< EF FE< NFLC; 9FK?L@E> K?<D LK 89LJ< ;<=@E@K@FEJ ALJK 8 C@KKC< 8E; K?@:

N8E;Jg@E8I>LD<EKJF=:FLIJ<EFK@EI<8C@KP

http://en.wikipedia.org/wiki/Image:Mars_Hubble.jpg

0,&+!'&+&! &,&+!'&+

5. Similarity Clusters

Followup to OK<EJ@FEJ8E;$EK<EJ@FEJ

*E:< LGFE 8 K@D< K?< G?@CFJFG?<IJ F= +C8KFcJ :8;<DP :C8@D<;K?8K K?< 9<JK ;<=@E@K@FE F= ?LD8E N8J 8 `=<8K?<IC<JJ 9@G<;a @Fe

><E<J F= .@EFG< 8CJF :8CC<; @F><E<J K?< PE@: @J J8@; KF ?8M<GIFDGKCP <O?@9@K<; 8 GCL:B<; :?@:B<E 8E; ;<:C8I<; `#<I< @J +C8KFcJD8Ea /?< +C8KFE@JKJ GIFDGKCP :?8E><; K?<@I ;<=@E@K@FE KF `8 =<8K?<IC<JJ9@G<;N@K?9IF8;E8@CJa

)F ;@:K@FE8IP EF <E:P:CFG<;@8 ?8J <MJK?8K ?LD8EJ ?8M< @E :FDDFE 2< ?8M< I<; 9CFF; =@M< =@E><IJ FE

<8:? F= KNF ?8E;J 9FEP JBLCCJ G8@IJ F= :?IFDFJFD<Jg9LK K?<J8D< D@>?K 9< J8@; F= FK?L8>< N< ?8IE<JJ :I@K@:8C =@JJ@FE I<8:K@FEJ 8J 8 JFLI:< F= <EPK?<J< K?@E>J D8P J<IM< FLK KF J@E>C< FLK FECP ?LD8EJ 9LK EFK 8CC ?LeD8EJgD8EP F= LJ ?8M< E<M?KJ<K F= E<:<JJ8IPe8E;eJL==@:@<EK ><E< J<HL<E:<J PFL :FLC; J@E>C< FLK8CC ?LD8EJ 8E; FECP ?LD8EJg8K C<8JK =FI EFNg9LK @K NFLC; JK@CC9<=8I=IFD all K?8K?LD8EJ?8M<@E:FDDFE

LK JF CFE> 8J PFL ;FEcK ?8GG<E KF 9< E<8I 8 GCL:B<; :?@:B<E J8P@E> `'FFB =FI =<8K?<IC<JJ 9@G<;Ja D8P J<IM< KF G@:B FLK 8 =<N ;FQ<E F= K?< G8IK@:LC8I K?@E>J K?8K 8I< ?LD8EJ 8J FGGFJ<; KF ?FLJ<J M8J<JJ8E;N@:?<J:8KJ:FCFIJFID8K?<D8K@:8CK?<FI<DJ

*E:< K?< ;<=@E@K@FE `=<8K?<IC<JJ 9@G<;a ?8J 9<<E 9FLE; KF JFD< particular =<8K?<IC<JJ 9@G<;J PFL :8E CFFB FMIFLG 8E; 9<>@E?8IM<JK@E> JFD< F= K?< other :?8I8:K<I@JK@:Jg9<PFE; D<I< =<8K?<Ie=I<< KNFC<>>@E<JJgK?8K K?< `=<8K?<IC<JJ 9@G<;Ja J<<D KF J?8I< @E:FDDFE /?< G8IK@:LC8I =<8K?<IC<JJ 9@G<;J K?8K PFL J<< J<<D KF 8CeJF LJ< C8E>L8>< 9L@C; :FDGC<O KFFCJ JG<8B :FD9@E8KFI@8C C8E>L8><

N@K? JPEK8O 9C<<; I<; 9CFF; @= GFB<; ;@< N?<E K?FIP `?LD8Ea >IFNJ I@:?<E<J =@E8CCP GI<J<EKJ ?@JGCL:B<; :?@:B<E N< 8I< EFK =FFC<; /?@J GCL:B<; :?@:B<E @J F9M@eFLJCPEFKJ@D@C8IKFK?<FK?<I`=<8K?<IC<JJ9@G<;Ja

http://lesswrong.com/lw/nj/similarity_clusters/ +8><bOK<EJ@FEJ8E;$EK<EJ@FEJc

h$= I@JKFK<C@8E CF>@: N<I< 8 >FF; DF;<C F= ?LD8E GJP:?FCF>PK?< +C8KFE@JKJ NFLC; ?8M< CFFB<; 8K K?< GCL:B<; :?@:B<E 8E; J8@;`4<JK?8KcJ8?LD8EN?8KcJPFLIGF@EKai

$= K?< first =<8K?<IC<JJ 9@G<; PFL J<< @J 8 GCL:B<; :?@:B<E K?<E PFL D8P <E; LG K?@EB@E> K?8K K?< M<I98C C89<C `?LD8Ea ;<EFK<J8 GCL:B<; :?@:B<E JF $ :8E DF;@=P DP KI<8JLI< D8G KF GF@EK KF`=<8K?<IC<JJ 9@G<;J N@K? 9IF8; E8@CJa 8E; @= $ 8D N@J< >F FE KF J8P`.<< @F><E<J FM? =8@ICP :CFJ<a

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DFE =KFFE KF :FEM?K F= EFK 8J 8 9FFB F= I@JKFK<C@8E:C8JJ ;<=@E@K@FEJ 9LK 8 9FFB F= ?@EKJ =FI D8K:?@E> M<I98C C89<CJ KFJ@D@C8I@KP :CLJK<IJ FI D8K:?@E> C89<CJ KF GIFG<IK@<J K?8K 8I< LJ<=LC@E;@JK@E>L@J?@E>J@D@C8I@KP:CLJK<IJ

+!%!$*!,1$-+,*+

6. Typicality and Asymmetrical Similarity

Followup to .@D@C8I@KPCLJK<IJ

@I;J =CP 2<CC <O:<GK FJKI@:?<J ;FEcK LK N?@:? @J 8 DFI< KPGe@:8C9@I;g8IF9@EFI8EFJKI@:?2?@:? @J 8 DFI< KPG@:8C :?8@I ;<JB :?8@I 8 IF:B@E> :?8@I FI 8 9<8E98>:?8@I

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!FI <O8DGC< @= PFL 8JB JL9A<:KJ KF GI<JJ 8 9LKKFE KF @E;@:8K< `KIL<aFI `=8CJ<a @E I<JGFEJ< KF JK8K<D<EKJ C@B< ` IF9@E @J 8 9@I;a FI `G<E>L@E @J 8 9@I;a I<8:K@FE K@D<J 8I< =8JK DP 9FFBJ 9LK $cD I<8JFE89CP JLI< DP JFLI:< FE K?@J @J '8BF== i /PG@:8C@KP D<8JLI<J :FII<C8K< N<CCLJ@E> ;@==<I<EK @EM<JK@>8K@M< D<K?F;JgI<8:K@FE K@D<J 8I< FE< <Oe8DGC< PFL :8E 8CJF 8JB G<FGC< KF ;@I<:KCP I8K< FE 8 J:8C< F= KF ?FN N<CC 8E <O8DGC< hC@B< 8 JG<:@=@: IF9@Ei =@KJ 8 :8K<>FIP hC@B<`9@I;ai

.F N< ?8M< 8 D<EK8C D<8JLI< F= KPG@:8C@KPgN?@:? D@>?K G<Ie?8GJ =LE:K@FE 8J 8 ?<LI@JK@:g9LK @J K?<I< 8 :FII<JGFE;@E> 9@8J N<:8ELJ<KFG@E@K;FNE

2<CC N?@:? F= K?<J< JK8K<D<EKJ JKI@B<J PFL 8J DFI< E8KLI8C` @J 8GGIFO@D8K<CP a FI ` @J 8GGIFO@D8K<CP a $= PFLcI<C@B< DFJK G<FGC< K?< =@IJK JK8K<D<EK J<<DJ KF D8B< DFI< J<EJ<h.8;F:B i !FI J@D@C8I I<8JFEJ G<FGC< 8JB<; KF I8K< ?FN J@D@C8I(<O@:F @J KF K?< 0E@K<; .K8K<J >8M< :FEJ@JK<EKCP ?@>?JK?8E G<FGC< 8JB<; KF I8K< ?FN J@D@C8I K?< 0E@K<; .K8K<J @J KF (<O@e:F h/M<IJBP8E;"8K@i

E; @= K?8K JK@CC J<<DJ ?8IDC<JJ 8 JKL;P 9P -@GJ hi J?FN<;K?8K G<FGC< N<I< DFI< C@B<CP KF <OG<:K 8 ;@J<8J< NFLC; JGI<8; =IFDIF9@EJ KF ;L:BJ FE 8E @JC8E; K?8E =IFD ;L:BJ KF IF9@EJ )FN K?@J@J EFK 8 logical @DGFJJ@9@C@KP 9LK @E 8 GI8>D8K@: J<EJ< N?8K<M<I ;@=e=<I<E:< J<G8I8K<J 8 ;L:B =IFD 8 IF9@E 8E; NFLC; D8B< 8 ;@J<8J< C<JJC@B<CP KF JGI<8; =IFD 8 ;L:B KF 8 IF9@E DLJK 8CJF 9< 8 ;@==<I<E:<

http://lesswrong.com/lw/nk/typicality_and_asymmetrical_similarity/ +8><b.@D@C8I@KPCLJK<IJc

9<KN<<E 8 IF9@E 8E; 8 ;L:B 8E; NFLC; D8B< 8 ;@J<8J< C<JJ C@B<CP KFJGI<8;=IFD8IF9@EKF8;L:B

4<J PFL :8E :FD< LG N@K? I8K@FE8C@Q8K@FEJ C@B< `2<CC K?<I<

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from the Third Annual Meeting of the Berkeley Linguistics Society, GGe <IB<C<P<IB<C<P'@E>L@JK@:J.F:@<KP

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7. The Cluster Structure of Thingspace

Followup to /PG@:8C@KP8E;JPDD<KI@:8C.@D@C8I@KP

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8. Disguised Queries

Followup to /?<CLJK<I.KIL:KLI<F=/?@E>JG8:<

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http://lesswrong.com/lw/nm/disguised_queries/ +8><b/?<CLJK<I.KIL:KLI<F=/?@E>JG8:<c

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10. How An Algorithm Feels From Inside

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http://lesswrong.com/lw/no/how_an_algorithm_feels_from_inside/

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http://lesswrong.com/lw/n1/allais_malaise/

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11. Disputing Definitions

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http://lesswrong.com/lw/np/disputing_definitions/ +8><b#FNEC>FI@K?D!<<CJ!IFD$EJ@;<c

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12. Feel the Meaning

Followup to @JGLK@E><=@E@K@FEJ

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http://lesswrong.com/lw/nq/feel_the_meaning/

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13. The Argument from Common Usage

Followup to !<<CK?<(<8E@E>

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14. Empty Labels

Followup to /?LD<EK=IFDFDDFE0J8><

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!I<; `4FLD<8EK?8KK?@E>FM<IK?<I<@J9CL<IFLE;=LQQP8E;ga(<`$EI@JKFK<C@8ECF>@:@KcJEFKJLGGFJ<;KFD8B<8 ;@==<I<E:<N?8KK?<GIFG<IK@<J8I<FIN?8K$:8CCK?<D/?8KcJN?P$cDALJKLJ@E>K?<C<KK<IJa

)<OK $ @EM<EK K?< I@JKFK<C@8E :8K<>FIP `Q8N8a N?@:? ;<J:I@9<JK?FJ< F9A<:KJ 8CC K?FJ< F9A<:KJ 8E; FECP K?FJ< F9A<:KJ N?@:? ?8M<GIFG<IK@<J8E;

(< `*9A<:K@JQ8N88E;a!I<; `E;@KcJ9CL<g$D<8EgKFFI@>?Ka(< `/?8KcJ@DGC@<;N?<E$J8P@KcJQ8N8a

!I<; `.K@CC$c;C@B<PFLKFJ8P@K<OGC@:@KCPa(< `*B8P *9A<:K@JQ8N88E;a

/?<E $ 8;; 8EFK?<I NFI; `PFB@<a N?@:? ;<J:I@9<J 8CC 8E; FECP F9A<:KJ K?8K 8I< 8E; 8E; K?< NFI; `O@GGFa N?@:? ;<J:I@9<J 8CC8E;FECPF9A<:KJN?@:?8I<9LKEFK

(< `*9A<:K@JQ8N88E;PFB@<9LKEFKO@GGFa!I<; `28@K@J@KCLD@E<J:<EK $D<8E@J@Ka

(< `4<J /?8K@JK?<FECPGFJJ@9@C@KPFEK?<@E=FID8K@FE>@M<Ea!I<; `$c;I8K?<IPFLJG<CC<;@KFLKa(< `!@E< *9A<:K@JQ8N8PFB@<8E;EFKO@GGFa!I<; `D8Q@E> 4FL:8EK<CC8CCK?8KALJK9PCFFB@E>a

http://lesswrong.com/lw/ns/empty_labels/ +8><b/?LD<EK=IFDFDDFE0J8><c

$DGI<JJ@M< @JEcK @K '<KcJ @EM<EK <M<E DFI< E<N NFI;J `FCFa@J 8E; PFB@< `DLEa @J 8E; O@GGF 8E; `D<IC8:;FE@8Ea @J9FCF8E;DLE

+F@EKC<JJCP :FE=LJ@E> $ K?@EB JF KFF '<KcJ I<GC8:< K?< C89<CJ N@K?K?<;<=@E@K@FEJ

`58N88E;a9<:FD<Jjk`FCF8E;a9<:FD<Jjjkk`(<IC8:;FE@8Ea9<:FD<JjjkkjjSkk

E; K?< K?@E> KF I<D<D9FI@<J @J K?8K j k @J K?< entire @E=FID8K@FE F= `Q8N8a $KcJ EFK

ALJK K?8K $ :8E M8IP K?< C89<C 9LK K?8K $ :8E ><K 8CFE> ALJK =@E< N@K?eFLK 8EP C89<C 8K 8CCgK?< ILC<J =FI I@JKFK<C@8E :C8JJ<J NFIB GLI<CP FE JKIL:KLI<J C@B< j k /F :8CC FE< F= K?<J< JKIL:KLI<J `Q8N8aFI 8KK8:? 8EP FK??K<JK ;@==<I<E:< KF K?< I@JKFK<C@8EILC<J

'<KcJ J8P K?8K `?LD8Ea @J KF 9< ;<=@E<; 8J 8 DFIK8C =<8K?<IC<JJ9@G<; /?<EK?< :C8JJ@:JPCCF>@JD NFLC;?8M<K?<=FID

CCjDFIK8CS=<8K?<IJ9@G<;8Ck8I<DFIK8C.F:I8K<J@J8jDFIK8CS=<8K?<IJ9@G<;8Ck/?<I<=FI<.F:I8K<J@JDFIK8C

/?< =<8K F= I<8JFE@E> CFFBJ 8 CFK C<JJ @DGI<JJ@M< EFN ;F<JEcK @K

#<I< K?< illusion of inference :FD<J =IFD K?< C89<CJ N?@:? :FEe:<8C K?< GI<D@J<J 8E; GI<K<E; KF EFM<CKP @E K?< :FE:CLJ@FE -<eGC8:@E> C89<CJ N@K? ;<=@E@K@FEJ I<M<8CJ K?< @CCLJ@FE D8B@E> M@J@9C<

K?< K8LKFCF>PcJ <DG@I@:8C LE?<CG=LCE<JJ 4FL :8E E<M<I J8P K?8K.F:I8K<J @J 8 jDFIK8C S=<8K?<IJ 9@G<;k LEK@C PFL ?8M< F9J<IM<; ?@DKF9<DFIK8C

/?<I<cJ 8E @;<8 N?@:? PFL D8P ?8M< EFK@:<; $ ?8K< K?8K `PFL:8E ;<=@E< 8 NFI; 8EP N8P PFL C@B<a /?@J @;<8 :8D< =IFD K?< I@JeKFK<C@8E EFK@FE F= :8K<>FI@<J J@E:< @= PFL =FCCFN K?< I@JKFK<C@8EILC<J exactly 8E; without flaw gN?@:? ?LD8EJ E<M<b/?<+8I89C<F=#<DCF:Bc

+8><b/?<+8I89C<F=#<DCF:Bc +8><b2FI;J8J#@;;<E$E=<I<E:<Jc

%(,1$$+

KC< BE<N G<I=<:KCP N<CC K?8K .F:I8K<J N8J ?LD8E <M<E K?FL>? K?8K N8JEcK ALJK@=@<; LE;@E8IP EFE?LD8E<EK@KP N<I< KF =FCCFN K?< ILC<J <O8:KCP K? K?<P :FLC;EcK J8P K?8K .F:I8K<J @J 8 jDFIK8C S=<8K?<IJ 9@G<;k LEK@C K?<P F9J<IM<;?@DKF9<DFIK8C

LK @KcJ EFK JF DL:? K?8K C89<CJ 8I< arbitrary @E K?< I@JKFK<C@8EJPJK<D 8J K?8K K?< I@JKFK<C@8E JPJK<D NFIBJ =@E< N@K?FLK any labels at all g@K :I8EBJ FLK <O8:KCP K?< J8D< JKI<8D F= K8LKFCF>@<J K?F@E> KF ?8M< 8E I@JKFK<C@8E GIFM<I9 8K 8CC K?<

GIFM<I9 J?FLC; 9< EFK `$ :8E ;<=@E< 8 NFI; 8EP N8P $ C@B<a EFI<M<E `<=@E@E> 8 NFI; E<M<I ?8J 8EP :FEJ<HL<E:<Ja 9LK I8K?<I`<=@E@K@FEJ;FEcKE<<;NFI;Ja

-%&6+-!,'/'*+

15. Taboo Your Words

Followup to DGKP'89<CJ

$E K?< >8D< /89FF h9P #8J9IFi K?< F9A<:K@M< @J =FI 8 GC8PL<JJ 8 NFI; NI@KK<E FE 8 :8I; N@K?FLK LJ@E> K?8K NFI; FI =@M< 8;;@K@FE8C NFI;J C@JK<; FE K?< :8I; !FI <O8DGC<

PFL D@>?K ?8M< KF ><K PFLI G8IKE K?< NFI;J `JGFIKa `98Ka `?@Ka `G@K:?a `98J<a FI F= :FLIJ< `98J<e98CCa

/?< <O@JK<E:< F= K?@J >8D< JLIGI@J<; D< N?<E $ ;@J:FM<I<; @K2?P NFLC;EcK PFL ALJK J8P `E 8IK@=@:@8C >IFLG :FE=C@:K @E N?@:? PFL

LJ< 8 CFE> NFF;<E :PC@E;8D< $c; 8CI<8;P 9<<EGI8:K@:@E>@K=FIP<8IJg8C9<@KN@K?8;@==<I<EKGLIGFJ<

4<JK<I;8P N< J8N ?FN I<GC8:@E> K<IDJ N@K? ;<=@E@K@FEJ :FLC;I<M<8C K?< <DG@I@:8C LEGIF;L:K@M@KP F= K?< :C8JJ@:8C I@JKFK<C@8E JPCeCF>@JD

CCjDFIK8CS=<8K?<IJ9@G<;k8I<DFIK8C

.F:I8K<J@J8jDFIK8CS=<8K?<IJ9@G<;k/?<I<=FI<.F:I8K<J@JDFIK8C

LKK?<GI@E:@GC<8GGC@<JDL:?DFI<9IF8;CP

C9<IK `KI<<=8CC@E>@E8;<J<IK<;=FI<JKD8B<J8 JFLE;a8IIP `KI<<=8CC@E>@E8;<J<IK<;=FI<JK;F<JEFKD8B<8JFLE;a

C<8ICP J@E:< FE< J8PJ `JFLE;a 8E; FE< J8PJ `SJFLE;a N< DLJK?8M< 8 :FEKI8;@:K@FE I@>?K LK JLGGFJ< K?8K K?

C9<IK `KI<<=8CC@E>@E8;<J<IK<;=FI<JKD8K:?<JjD<D9<IJ?@GK<JKK?@J<M<EK><E<I8K<J8:FLJK@:

http://lesswrong.com/lw/nu/taboo_your_words/

+8><bDGKP'89<CJc +8><b/?<+8I89C<F=#<DCF:Bc

M@9I8K@FEJka8IIP `KI<<=8CC@E>@E8;<J<IK<;=FI<JK;F<JEFKD8K:?jD<D9<IJ?@GK<JKK?@J<M<EK><E<I8K<J8L;@KFIP

<OG<I@<E:<Jka

)FN K?<I< @J EF CFE> K?< NFI; sound $= `8:FLJK@:

M@9I8K@FEJa :8D< @EKF ;@JGLK< N< NFLC; ALJK GC8P /89FF 8>8@E 8E;J8P `GI<JJLI< N8M<J @E 8 D8K<I@8C D<;@LDa @= E<:<JJ8IP N< NFLC;GC8P /89FF 8>8@E FE K?< NFI; `N8M<a 8E; I<GC8:< @K N@K? K?< N8M<<HL8K@FE h+C8P /89FF FE `8L;@KFIP <OG<I@<E:<a 8E; PFL ><K `/?8K=FID F= J<EJFIP GIF:<JJ@E> N@K?@E K?< ?LD8E 9I8@E N?@:? K8B<J 8J

@EGLK8C@E<8IK@D<J<I@<JF==I<HL<E:PD@O<JaiLK JLGGFJ< FE K?< FK?LD<EK

C9<IK `.F:I8K<JD8K:?<JK?<:FE:<GKjD<D9<IJ?@GK<JKK?@JG<IJFEN@CC;@<8=K<I;I@EB@E>?<DCF:Bka8IIP `.F:I8K<JD8K:?<JK?<:FE:<GKjD<D9<IJ?@GK<JKK?@JG<IJFEN@CCEFK;@<8=K<I;I@EB@E>?<DCF:Bka

)FN C9<IK 8E; 8IIP ?8M< 8 JL9JK8EK@M< :C8J? F= <OG<:K8K@FEJ8 ;@==<I<E:< @E N?8K K? 8=K?K EFK EFK@:< K?@J @= K?<K 8 M<IP ;@==<I<EK G@:KLI< F= N?8K G<FGC< 8>I<< FI ;@J8>I<<89FLK ;<G<E;@E> FE N?<K?I< K?< K<JKcJe<P<eM@<N hC9<IKcJ D<D9<IJ?@G K<JK @J 8:FLJK@: M@e

9I8K@FEJ8IIPcJ@J8L;@KFIP<OG<I@<E:<i"<K KF><K?<E:< @E K?@IKP P<8IJ 8E; $ NFLC;

>L<JJ K?8K 8K C<8JK ?8C= F= K?<D N@CC J8P P<J $= PFL C<8M< @K 8K K?8KK?<PcCC J?8B< ?8E;J 8E; :FE>I8KLC8K< K?<DJ<CM<J FE K?<@I :FEJ<EeJLJ LK D8B< K?< K<ID `IK@=@:@8C $EK<CC@><E:<a K89FF 8E; 8JBK?<D KF ;<J:I@9< what K? NFI;JC@B< `:FDGLK<IJa FI `K?@EBa 8E; PFL D@>?K =@E; HL@K< 8 :FE=C@:K F= <OG<:K8K@FEJ ?@;@E> LE;<b"L<JJ@E>K?</<8:?<IcJ+8JJNFI;c

-%&6+-!,'/'*+

K?8K FK?>cJ :FDG@C8K@FE F= ;<=@eE@K@FEJF=`@EK<CC@><E:<a

/?< @CCLJ@FE F= LE@KP 8:IFJJ I<C@>@FEJ :8E 9< ;@JG<CC<; 9P D8B@E>

K?< K<ID `"F;a K89FF 8E; 8JB@E> K?<D KF J8P N?8K @K @J K? K?< NFI; `=8@K?a K89FF 8E; 8JB@E> K?<D N?P K?? DFJKCP K?E@K@M<CP QFFD@EFE8E8L;@FI<:FI;@E>

2?<E PFL =@E; PFLIJ<C= @E G?@CFJFG?@:8C ;@==@:LCK@<J K?< =@IJKC@E< F= ;<=<EJ< @J EFK KF ;<=@E< PFLI GIF9C<D8K@: K<IDJ 9LK KF J<<

N?<K? K?FJ< K<IDJ 8K 8CC *I 8EP F=

K?<@I J?FIK JPEFEPDJ E; 9< :8I<=LC EFK KF C<K PFLIJ<C= @EM<EK 8 E<N NFI; KF LJ< @EJK<8; <J:I@9< FLKN8I; F9J<IM89C<J 8E; @EK<I@eFI D<:?8E@JDJ ;FEcK LJ< 8 J@E>C< ?8E;C< N?8K<M<E<I8K< 8E 8GG8I<EK:FE=C@:K (FJK G?@CFJFG?<IJ NFLC; 8;M@J< C9<IK 8E; 8IIP KF KIP KF ;<=@E< <O8:KCP N?8K K?I<8K C<E>K? $ NFLC; 8;M@J<

C9<IK 8E; 8IIP KF ;<J:I@9< N?8K @K @J K?8K K? K?< G?I8J< `=I<< N@CCa 8K 8CC h$= PFL N8EKKF KIP K?@J 8K ?FD< PFL J?FLC; 8CJF 8MF@; K?< NFI;J `:?FFJ<a `8:Ka`;<:@;<a`;<K<ID@E<;a`I<JGFEJ@9C<aFI8EPF=K?<@IJPEFEPDJi

/?@J @J FE< F= K?< EFEJK8E;8I; KFFCJ @E DP KFFC9FO 8E; @E DP ?LD9C< FG@E@FE @K NFIBJ way way 9<KK<KN?8KPFLG8P=FI

http://www.singinst.org/blog/2007/09/30/three-major-singularity-schools/

http://arxiv.org/abs/0706.3639 +8><b<C@<=@E<C@<=c

,''1'-* /'*+

16. Replace the Symbol with the Substance

Continuation of /89FF4FLI2FI;J

Followup to *I@>@E8C.<<@E> 'FJK+LIGFJ<J

2?8K ;F<J @K K8B< KFg8J @E P<JK<I;8PcJ <O8DGC<gJ<< 8 `98J<98CC >8D<a 8J `E 8IK@=@:@8C >IFLG :FE=C@:K @E N?@:? PFL LJ< 8 CFE> NFF;e<E :PC@E;F8C @J EFK KF =@E; 8 JPEFEPD K?8K @JEcK FE K?<:8I; 9LK KF =@E; 8 N8P F= ;<J:I@9@E> N@K?FLK K?< JK8E;8I; :FE:<GKe

?8E;C<4FL ?8M< KF M@JL8C@Q< 4FL ?8M< KF D8B< PFLI D@E;cJ <P< J<<

K?< ;<K8@CJ 8J K?FL>? CFFB@E> =FI K?< =@IJK K@D< 4FL ?8M< KF G<Ie=FID8E *I@>@E8C.<<@E>

$J K?8K 8 `98Ka )F @KcJ 8 CFE> IFLE; K8G<I@E> NFF;<E IF;E8IIFN@E>8KFE<<E;JFK?8K8?LD8E:8E>I8JG8E;JN@E>@K

$J K?8K 8 `98CCa )F @KcJ 8 C<8K?<Ie:FM<I<; JG?<IF@; N@K? 8 JPDeD<KI@:8C JK@K:?@E> G8KK<IE ?8I; 9LK EFK D<K8Ce?8I; N?@:? JFD<FE<:8E>I8JG8E;K?IFNFIJKI@B<N@K?K?<NFF;<EIF;FI:8K:?

I< K?FJ< `98J<Ja )F K?<PcI< =@O<; GFJ@K@FEJ FE 8 >8D< =@<C;K?8K GC8P<IJ KIP KF ILE KF 8J HL@:BCP 8J GFJJ@9C< 9<:8LJ< F= K?<@I J8=<eKPN@K?@EK?<>8D<cJ8IK@=@:@8CILC<J

/?< :?@<= F9JK8:C< KF G<I=FID@E> 8E FI@>@E8C J<<@E> @J K?8K PFLID@E; 8CI<8;P ?8J 8 E@:< E<8K JLDD8IP 8 E@:< C@KKC< <8JPeKFeLJ< :FEe:<GK ?8E;C< '@B< K?< NFI; `98J<98CCa FI `98Ka FI `98J<a $K K8B<J8E <==FIK KF JKFG PFLI D@E; =IFD JC@;@E> ;FNE K?< =8D@C@8I G8K? K?<<8JP G8K? K?< G8K? F= C<8JK I<J@JK8E:< N?<I< K?< JD8CC =<8KLI<C<JJ

NFI; ILJ?<J @E 8E; F9C@K<I8K<J K?< ;<K8@CJ PFLcI< KIP@E> KF J<< NFI; @KJ<C= :8E ?8M< K?< ;<JKIL:K@M< =FI:< F= :C@:?< 8 NFI; @KJ<C= :8E:8IIPK?<GF@JFEF=8 :8:?<;K?FL>?K

http://lesswrong.com/lw/nv/replace_the_symbol_with_the_substance/ +8><b/89FF4FLI2FI;Jc +8><b*I@>@E8C.<<@E>c http://lesswrong.com/lw/le/lost_purposes/ +8><b*I@>@E8C.<<@E>c

+8><b-8K@FE8C@KP8E;K?<E>C@J?'8E>L8><c +8><b8:?<;/?FL>?KJc

+C8P@E> K?< >8D< F= /89FF g9<@E> 89C< KF ;<J:I@9< N@K?FLKLJ@E> K?< JK8E;8I; GF@EK<IC89<C?8E;C<g@J FE< F= K?< fundamental I8K@FE8C@JK :8G8:@K@<J $K F::LG@<J K?< J8D< GI@DFI;@8C C<M<C 8J K?<

?89@K F= :FEJK8EKCP 8JB@E> `2?Pa FI `2?8K ;F<J K?@J 9<C@<= D8B<D<8EK@:@G8K<a

/?<8IK@J:CFJ<CPI<C8K<;KF

[ +I8>D8K@JD9<:8LJ<J<<@E>@EK?@JN8PF=K<E>@M<JPFL8 DL:?:CFJ<I:FEE<:K@FEKF 8EK@:@G8K<;<OG<I@<E:<I8K?<IK?8E GIFGFJ@K@FE8C9<C@<=

[ -<;L:K@FE@JD9<:8LJ<J<<@E>@EK?@JN8PF=K<E=FI:<JPFLKF;IFG;FNEKF8CFN<IC<M<CF=FI>8E@Q8K@FECFFB8KK?<

G8IKJ@EJK<8;F=PFLI<P<JB@GG@E>FM<IK?<N?FC<[ #L>>@E>K?<HL<IP 9<:8LJ<NFI;JF=K<E;@JKI8:KPFL=IFDK?<HL<JK@FEPFLI<8CCPN8EKKF8JB

[ MF@;@E> :8:?<;K?FL>?KJN?@:?N@CCILJ?@ELJ@E> JK8E;8I;NFI;JJFPFL:8E9CF:BK?<D9PK89FF@E> JK8E;8I;NFI;J

[ /?<NI@K<IcJILC<F=`.?FN;FEcKK<CCaN?@:??8JGFN<I8DFE>I8K@FE8C@JKJ

[ E; EFKCFJ@E>J@>?KF=PFLIFI@>@E8CGLIGFJ<

#FN:FLC;K89FF@E>8NFI;?<CGPFLB<<GPFLIGLIGFJ<!IFD 'FJK+LIGFJ<J

JPFLI<8;K?@JJFD<PFLE>D8EFINFD8E@JJ@KK@E>8K8;<JB@E8LE@M<IJ@KP<8IE<JKCPJKL;P@E>D8K<I@8CK?8E;EF@EK<I<JK@EBEFN@E>=FI@KJFNEJ8B< /?<PN8EK8?@>?eG8P@E>AF98E;K?<?@>?eG8P@E>AF9I<HL@I<J8G@<:<F=G8G<I8E;K?<G@<:<F=G8G<II<HL@I<J8GI<M@FLJD8JK<IcJ;<>I<<8E;K?<D8JK<IcJ;<>I<<I<HL@I<J898:?<CFIcJ;<>I<<8E;K?<LE@M<IJ@KPK?8K>I8EKJK?<98:?<CFIcJ;<>I<<I<HL@I<JPFLKFK8B<8:C8JJ@EK?e:<EKLIPBE@KK@E>G8KK<IEJKF

>I8;L8K< .FK?<P;@C@><EKCPJKL;P@EK<E;@E>KF=FI><K@K

+8><b/89FF4FLI2FI;Jc +8><b(8B@E><C@<=J+8P-<EKh@EEK@:@G8K<;OG<I@<E:<Jic

+8><b<C@<=@E<C@<=c +8><b#L>K?<,L<IPc +8><b8:?<;/?FL>?KJc

http://lesswrong.com/lw/le/lost_purposes/ http://lesswrong.com/lw/le/lost_purposes/

* ($,+1%'$/!,,+-+,&

8CCK?<DFD<EKK?<=@E8C<O8D@J8;D@E@JK<I<;9LKJK@CCJ<I@FLJCPNFIB@E>8N8P9<:8LJ<K?F@E> KF `J:?FFCa /F ><K 8E `<;L:8K@FEa <E;@E> @E 8 `;<>I<<a C8EB FLK K?< =FI9@;;<E NFI;J 8E; 8CC K?<@I F9M@FLJJPEFEPDJ M@JL8C@Q< K?< 8:KL8C ;<K8@CJ 8E; PFLcI< DL:? DFI< C@B<CP KF EFK@:< K?8K `J:?FFCa :LII<EKCP J<<DJ KF :FEJ@JK F= J@KK@E> E<OKKF 9FI<; K<<E8><IJ C@JK<E@E> KF D8K<I@8C PFL 8CI<8;P BEFN K?8K 8 `;<>I<<a @J 8 G@<:< F= G8G FE @K 8E; K?8K `<;Le:8K@FEa@J=FI><KK@E>K?<D8K<I@8C8JJFFE8JPFLcI<K<JK<;FE@K

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http://lesswrong.com/lw/lc/leaky_generalizations/

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http://yudkowsky.net/bayes/truth.html

* ($,+1%'$/!,,+-+,&

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+8><b/NFLCK&F8EJc http://lesswrong.com/lw/nc/newcombs_problem_and_regret_of_rationality/

-%&6+-!,'/'*+

17. Fallacies of Compression

Followup to -<GC8:<K?<.PD9FCN@K?K?<.L9JK8E:<

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http://lesswrong.com/lw/nw/fallacies_of_compression/

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-%&6+-!,'/'*+

18. Categorizing Has Consequences

Followup to !8CC8:@<JF=FDGI<JJ@FE

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http://lesswrong.com/lw/nx/categorizing_has_consequences/ +8><b!8CC8:@<JF=FDGI<JJ@FEc

http://en.wikipedia.org/wiki/Japanese_blood_type_theory_of_personality +8><b"L8I;@8EJF=K?</ILK?c

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19. Sneaking in Connotations

Followup to 8K<>FI@Q@E>#8JFEJ<HL<E:<J

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http://lesswrong.com/lw/ny/sneaking_in_connotations/

+8><b8K<>FI@Q@E>#8JFEJ<HL<E:<Jc +8><b/?<+8I89C<F=#<DCF:Bc

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-%&6+-!,'/'*+

20. Arguing “By Definition”

Followup to .E<8B@E>@EFEEFK8K@FEJ

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http://lesswrong.com/lw/nz/arguing_by_definition/ +8><b.E<8B@E>@EFEEFK8K@FEJc +8><b@J>L@J<;,L<I@<Jc +8><b.E<8B@E>@EFEEFK8K@FEJc

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$= PFL >F FE @EJ@JK@E> `LK .F:I8K<J @J 8 ?LD8E 8E; ?LD8EJ by definition, 8I< DFIK8Ca K?<E N?8K PFLcI< I<8CCP KIP@E> KF ;F @J 9CLIFLK <M<IPK?@E> PFL BEFN 89FLK .F:I8K<J except K?< =8:K F= ?@J ?LeD8E@KPg@EJ@JK K?8K K?< FECP :FII<:K GI<;@:K@FE @J K?< FE< PFL NFLC;D8B< @= PFL BE<N EFK?@E> 89FLK .F:I8K<J except K?8K ?< N8J ?LD8E

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)FK <M<IP G@<:< F= E<N <M@;<E:< D8B<J 8 J@>E@=@:8EK ;@==<I<E:<F= :FLIJ< $= $ J<< K?8K .F:I8K<J ?8J E@E< =@E><IJ K?@J @JEcK >F@E> KFEFK@:<89CP :?8E>< DP <JK@D8K< F= ?@J MLCE<I89@C@KP KF ?<DCF:B 9<e:8LJ< $cCC <OG<:K K?8K K?< N8P .F:I8K<J CFJK ?@J =@E><K?< I<JK F= ?@J 9@F:?<D@JKIP E; K?@J @J KIL< whether or not K?< ;@:eK@FE8IPcJ ;<=@E@K@FE J8PJ K?8K ?LD8E 9<@E>J ?8M< K<E =@E><IJ /?<C<>8C @E=<I<E:< @J 98J<; FE K?< :CLJKP not N?8K K?< ;@:K@FE8IP <;@KFI

NI@K<J;FNEEFI<M<E`:FDDFELJ8><a

+8><b-<GC8:<K?<.PD9FCN@K?K?<.L9JK8E:<c

-%&6+-!,'/'*+

)FN FI;@E8I@CP N?<E PFLcI< ;F@E> K?@J right g@E 8 legitimate N8PgPFL ALJK J8P `/?< :FE@@E< 8CB8CF@; =FLE; @E ?<DCF:B GIFe;L:<J DLJ:LC8I G8I8CPJ@J @E ?LD8EJ I<JLCK@E> @E ;<8K? 9P 8JG?POe

@8K@FEa *I DFI< J@DGCP `#LD8EJ 8I< MLCE<I89C< KF ?<DCF:Ba/?8KcJ?FN@KcJLJL8CCPJ8@;@E8 legitimate 8I>LD<EK

2?<E NFLC; JFD<FE< =<<C K?< E<<; KF strengthen K?< 8I>LD<EK N@K? K?< <DG?8K@: G?I8J< `9P ;<=@E@K@FEa h$< `#LD8EJ 8I< MLCeE<I89C< KF ?<DCF:B by definition! i 2?P N?<E K?< @E=<II<; :?8I8:eK<I@JK@: ?8J 9<<E :8CC<; @EKF ;FL9Kg.F:I8K<J ?8J 9<<E J<<E :FEJLCKe@E> ?<I9FCF>@JKJg8E; JF K?< JG<8B?K<E K?<

M@J<F=CF>@:

.F N?<E PFL J<< `9P ;<=@E@K@FEa LJ<; C@B< K?@J @K LJL8CCP D<8EJ

`!FI><K N?8K PFLcM< ?<8I; 89FLK .F:I8K<J :FEJLCK@E> ?<I9FCFe >@JKJg?LD8EJ by definition, 8I<DFIK8Ca

+<FGC< =<<C K?< E<<; KF JHL<<Q< K?< 8I>LD<EK FEKF 8 J@E>C<:FLIJ< 9P J8P@E> `EP + 9P ;<=@E@K@FE ?8J GIFG<IKP ,a FE <O8:KCP K?FJ< F::8J@FEJ N?<E K?

.F KFF N@K? K?< 8I>LD<EK `3 by definition, @J 8 4a > `K?<e

@JKJ 9<C@<M< K?8K "F; ;F<JEcK <O@JK K?<I<=FI< 8K?<@JKJ ?8M< 9<C@<=J89FLK "F; 9<:8LJ< 8 E<>8K@M< 9<C@<= @J JK@CC 8 9<C@<= K?<I<=FI< 8K?<e@JD 8JJ<IKJ 8EJN<IJ KF K?<FCF>@:8C HL<JK@FEJ K?<I<=FI< 8K?<@JD @Jby definition, 8I<C@>@FEa

4FL NFLC;EcK =<<C K?< E<<; KF J8P `#@E;L@JD by definition, @J 8 I<C@>@FEa 9<:8LJ< N<CC F= :FLIJ< #@E;L@JD @J 8 I<C@>@FE $KcJ EFKALJK8I<C@>@FE`9P;<=@E@K@FEa@KcJC@B<8E actual I<C@>@FE

K?<@JD ;F<J EFK I<J<D9C< K?< :<EKI8C D<D9<IJ F= K?< `I<C@e >@FEa :CLJK@FE by definition, PFL D@>?K >F 8IFLE; K?@EB@E> K?8K 8K?<@JD wasn’t 8 I<C@e >@FE /?8KcJ N?P PFLcM< >FK KF :ILJ? 8CC FGGFJ@K@FE 9P GF@EK@E> FLKK?8K `K?<@JD @J 8 I<C@>@FEa @J KIL< by definition 9<:8LJ< @K @JEcK KIL<8EPFK?<IN8P

2?@:? @J KF J8P +<FGC< @EJ@JK K?8K `3 by definition, @J 8 4a FEK?FJ< F::8J@FEJ N?<E K?<PcI< KIP@E> KF JE<8B @E 8 :FEEFK8K@FE F= 4K?8K @JEcK ;@I<:KCP @E K?< ;<=@E@K@FE 8E; 3 ;F<JEcK CFFB 8CC K?8K DL:?C@B<FK?<ID<D9<IJF=K?<4:CLJK<b.E<8B@E>@EFEEFK8K@FEJc

*-!&41!&!,!'&5

*M KI8:B F= ?FN F=K<E K?@J G?I8J< @J LJ<; :FII<:KCP M<IJLJ @E:FII<:KCPgK?FL>? EFK

N@K? C@K<I8C JK8K@JK@:J $ =<8I LK <P<98CC@E> JL>><JKJ K?8K LJ@E> K?<

G?I8J< by definition, 8EPN?<I< FLKJ@;< F= D8K? @J 8DFE> K?< DFJK8C8ID@E> J@>E8CJ F= =C8N<; 8I>LD<EK $cM< <M?K LGK?<I< N@K? `#@KC<I` `"F;a `89JFCLK<CP :<IK8@Ea 8E; `:8EcK GIFM<K?8Ka

/?@J ?<LI@JK@: F= =8@CLI< @J EFK G<I=<:KgK?< =@IJK K@D< $ <M<IJGFKK<; 8 :FII<:K LJ8>< FLKJ@;< F= D8K? @K N8J 9P -@:?8I; !<PEeD8E 8E; J@E:< K?<E $cM< JGFKK<; DFI< LK PFLcI< GIF989CP 9<KK<IF== ALJK ;<C<K@E> K?< G?I8J< `9P ;<=@E@K@FEa =IFD PFLI MF:89LeC8IPg8E; always FE 8EP F::8J@FE N?<I< PFL D@>?K 9< K<DGK<; KF

J8P @K @E @K8C@:J FI =FCCFN<; N@K? 8E <O:C8D8K@FE D8IB /?8KcJ 8 98;@;<8 by definition!

http://www.catb.org/jargon/html/G/Godwins-Law.html

-%&6+-!,'/'*+

21. Where to Draw the Boundary?

Followup to I>L@E>`P<=@E@K@FEa

/?<FE<:FD<JKFPFL8E; J8PJ

'FE>?8M<$GFE;<I<;K?<D<8E@E>F=K?<NFI;`IKa8E;8KC8JK$cM<=FLE;N?8KJ<<DJKFD<8J8K@J=8:KFIP ;<=@E@K@FE`IK@JK?8KN?@:?@J;<J@>E<;=FIK?<GLIGFJ<F=:I<8K@E>8I<8:K@FE@E8E8L;@<E:<a

Just because there’s a word “art” doesn’t mean that it has a meaning, floating out there in the void, which you can discover by finding the right definition.

$K =<<CJK?8KN8P 9LK@K@JEFKJF

2FE;<I@E> ?FN KF define a word D<8EJ PFLcI< CFFB@E> 8K K?<GIF9C<D K?< NIFE> N8PgJ<8I:?@E> =FI K?< DPJK<I@FLJ <JJ<E:< F=

N?8K@J@E=8:K8 :FDDLE@:8K@FEJ@>E8C

)FN K?<I< is 8 I<8C :?8CC<E>< N?@:? 8 I8K@FE8C@JK D8P C<>@K@D8K<eCP 8KK8:B 9LK K?< :?8CC<E>< @J EFK KF =@E; 8 J8K@J=8:KFIP ;<=@E@K@FEF= 8 NFI; /?< I<8C :?8CC<E>< :8E 9< GC8P<; 8J 8 J@E>C<eGC8P8D<

N@K?FLK JG<8B@E> 8CFL; /?< :?8CC<E>< @J =@>LI@E> FLK N?@:? K?@E>J8I< J@D@C8I KF <8:? FK?<IgN?@:? K?@E>J 8I< :CLJK<I<; KF><K?<Ig8E;JFD<K@D<JN?@:?K?@E>J?8M<8:FDDFE:8LJ<

$= PFL ;<=@E< `<CL:KIFDL>E<K@JDa KF @E:CL;< C@>?KE@E> @E:CL;<:FDG8JJ<J <O:CL;< C@>?K 8E; @E:CL;< (<JD<IcJ `8E@D8C D8>eE<K@JDa hN?8K N< EFN :8CC ?PGEFJ@Ji K?<E PFL N@CC ?8M< JFD< KIFLe9C< 8JB@E> `#FN ;F<J <C<:KIFDL>E<K@JD NFIBa 4FL ?8M< CLDG<;KF><K?J N?@:? ;F EFK 9<CFE> KF><K?E<K@JD @J 8 wrong word, 8 9FLE;e8IP @E K?@E>JG8:< K?8K CFFGJ 8IFLE; 8E; JN<IM<J K?IFL>? K?< :CLJeK<IJ8:LKK?8K=8@CJKF:8IM<I<8C@KP8CFE>@KJE8KLI8CAF@EKJ

http://lesswrong.com/lw/o0/where_to_draw_the_boundary/ +8><bI>L@E>`P<=@E@K@FEac http://lesswrong.com/lw/nw/fallacies_of_compression/ia9 +8><b!<<CK?<(<8E@E>c

+8><b/?LD<EK=IFDFDDFE0J8><c +8><b/?<CLJK<I.KIL:KLI<F=/?@E>JG8:<c

!@>LI@E> N?<I< KF :LK I<8C@KP @E FI; K?<AF@EKJg this @J K?< GIF9C<D NFIK?P F= 8 I8K@FE8C@JK $K @J N?8K G<FGC< should 9< KIP@E> KF ;F N?<E K?

<JJ<E:<F=8NFI; E; D8B< EF D@JK8B< @K @J 8 scientific :?8CC<E>< KF I<8C@Q< K?8K

PFL E<<; 8 J@E>C< NFI; KF ;<J:I@9< 9I<8K?@E> 8E; =@I< .F ;F EFKK?@EBKF:FEJLCKK?<;@:K@FE8IP<;@KFIJ=FIK?8K@JEFKK?<@IAF9

2?8K @J `8IKa LK K?<I< @J EF <JJ<E:< F= K?< NFI; =CF8K@E> @EK?<MF@;

+<I?8GJ PFL :FD< KF D< N@K? 8 CFE> C@JK F= K?< K?@E>J K?8K PFL:8CC`8IKa8E;`EFK8IKa

/?< Little Fugue in G Minor: IK GLE:?@EK?<EFJ< )FK8IKJ:?<IcJ Relativity: IK

=CFNI8DD@E>C8E>L8>< IK

:IFJJ=CF8K@E>@ELI@E< )FK8IK %8:B18E:<cJ Tschai EFM<CJ IK(F;<IEIK )FK8IK

E; PFL J8P KF D< `$K =<<CJ @EKL@K@M< KF D< KF ;I8N K?@J 9FLE;e8IP 9LK $ ;FEcK BEFN N?Pg:8E PFL =@E; D< 8E @EK<EJ@FE K?8KD8K:?<J K?@J <OK<EJ@FE 8E PFL >@M< D< 8 simple ;<J:I@GK@FE F= K?@J9FLE;8IPa

.F $ I<GCP `$ K?@EB @K ?8J KF ;F N@K? 8;D@I8K@FE F= :I8=KJD8EeJ?@G NFIB >F@E> @E 8E; NFE; FLK 2?8K K?< @E:CL;<;@K<DJ ?8M< @E :FDDFE @J K?< J@D@C8I 8<JK?<K@: <DFK@FEJ K?8K K?JL:?8E<DFK@FEa$J K?@J ?<CG=LC FI @J @K ALJK :?<8K@E> 8K /89FF $ NFLC; 8I>L<

K?8K K?< C@JK F= N?@:? ?LD8E <DFK@FEJ 8I< FI 8I< EFK aesthetic @J =8IDFI< :FDG8:K K?8E K?< C@JK F= <M<IPK?@E> K?8K @J FI @JEcK 8IK 4FLD@>?K 9< 89C< KF J<< K?FJ< <DFK@FEJ C@>?K@E> LG 8E =(-$ J:8Eg$J8PK?@J9PN8PF=<DG?8J@Q@E>K?8K<DFK@FEJ8I<EFK<K?<I<8C

http://lesswrong.com/lw/hq/universal_fire/

+8><b-<GC8:<K?<.PD9FCN@K?K?<.L9JK8E:<c +8><b/89FF4FLI2FI;Jc

-%&6+-!,'/'*+

LK F= :FLIJ< DP ;<=@E@K@FE F= 8IK @J EFK K?< I<8C GF@EK /?< I<8CGF@EK @J K?8K PFL :FLC; N<CC ;@JGLK< <@K?J ?8M<@E :FDDFE N?8K K? @Ka /?8K NFLC; 9<;@JGLK@E> DP @EK<EJ@FE DP 8KK<DGK KF ;I8N 8 :LIM< K?IFL>? K?<;8K8 GF@EKJ 4FL NFLC; J8P `4FLI <HL8K@FE D8P IFL>?CP =@K K?FJ<GF@EKJ9LK@K@JEFKK?<KIL<><E<I8K@E>;@JKI@9LK@FEa

*I PFL :FLC; ;@JGLK< DP <OK<EJ@FE 9P J8P@E> `.FD< F= K?<J<K?@E>J ;F 9<CFE> KF><K?<Ig$ :8E J<< N?8K PFLcI< ><KK@E> 8Kg9LKK?< +PK?FE C8E>L8>< J?FLC;EcK 9< FE K?< C@JK 8E; (F;<IE IKJ?FLC; 9<a h/?@J NFLC; D8IB PFL 8J 8 >LCC@9C< G?@C@JK@E< 9LK PFL:FLC; 8I>L< @Ki #<I< K?< GI<JLDGK@FE @J K?8K K?<I< @J @E;<<; 8ELE;<ICP@E> :LIM< K?8K ><E<I8K<J K?@J 8GG8I<EK C@JK F= J@D@C8I 8E; ;@JeJ@D@C8I K?@E>JgK?8K K?<I< @J 8 I?PD< 8E; I<8JFE even though you haven’t said yet where it comes from g9LK $ ?8M< LEN@KK@E>CP CFJK K?<I?PK?D8E;@E:CL;<;JFD<;8K8GF@EKJ=IFD8;@==<I<EK><E<I8KFI

'FE> 9<=FI< PFL know N?8K @K @J K?8K <C<:KI@:@KP 8E; D8>E<K@JD?8M< @E :FDDFE PFL D@>?K JK@CC JLJG<:Kg98J<; FE JLI=8:< 8GG<8Ie

8E:<JgK?8K`8E@D8CD8>E<K@JDa;F<JEFK9<CFE>FEK?<C@JK*E:< LGFE 8 K@D< @K N8J K?FL>?K K?8K K?< NFI; `=@J?a @E:CL;<;

;FCG?@EJ )FN PFL :FLC; GC8P K?< F?eJFe:C<MLLGG@<J J?8IBJ ;FCG?@EJ KIFLKm @J ALJK 8 C@JKgPFL :8EcK J8P K?8K 8 C@JK @J wrong. $ :8E GIFM< @E J<K K?<FIP K?8KK?@J C@JK <O@JKJ .F DP ;<=@E@K@FE F= fish N?@:? @J J@DGCP K?@J <OK<EeJ@FE8CC@JK:8EEFKGFJJ@9CP9<bNIFE>c8JPFL:C8@Da

*I PFL :FLC; JKFG GC8P@E> E@KN@K >8D<J 8E; 8;D@K K?8K ;FCG?@EJ;FEcK9<CFE>FEK?<=@J?C@JK

4FL :FD< LG N@K? 8 C@JK F= K?@E>J K?8K feel J@D@C8I 8E; K8B< 8 >L<JJ 8K N?P K?@J @J JF LK N?<E PFL =@E8CCP ;@J:FML<JJ N8J NIFE> $KD8P<M<EKLIEFLKK?8KPFLIC@JKN8JNIFE>

4FL :8EEFK ?@;< 9<?@E; 8 :FD=FIK@E> J?@<C; F= :FII<:Ke9Pe;<=@eE@K@FE FK? <OK<EJ@FE8C ;<=@E@K@FEJ 8E; @EK<EJ@FE8C ;<=@E@K@FEJ :8E9<NIFE>:8E=8@CKF:8IM<I<8C@KP8KK?<AF@EKJ

+8><bOK<EJ@FEJ8E;$EK<EJ@FEJc

/*,'*/,'-&*1

8K<>FI@Q@E> @J 8 >L<JJ@E> <E;<8MFI @E N?@:? PFL :8E D8B< D@JeK8B<J JF @KcJ N@J< KF 9< 89C< KF 8;D@K =IFD 8 K?<FI<K@:8C JK8E;GF@EKK?8KPFLI;<=@E@K@FEe>L<JJ<J:8E9<`D@JK8B<Ea

-%&6+-!,'/'*+

22. Entropy, and Short Codes

Followup to 2?<I<KFI8NK?<FLE;8IP

.LGGFJ< PFL ?8M< 8 JPJK<D 3 K?8KcJ <HL8CCP C@B<CP KF 9< @E 8EP F= GFJJ@9C<JK8K<J

l33333333m

/?<I<cJ 8E <OKI8FI;@E8I@CP L9@HL@KFLJ HL8EK@KPg@E G?PJ@:JD8K?<D8K@:J 8E; <M<E 9@FCF>Pg:8CC<; entropy 8E; K?< <EKIFGP F= 3 @J 9@KJ /?@J D<8EJ K?8K FE 8M<I8>< N<cCC ?8M< KF 8JB P<JeFIeEF HL<JK@FEJ KF =@E; FLK 3cJ M8CL< !FI <O8DGC< JFD<FE< :FLC; K<CCLJ3cJM8CL<LJ@E>K?@J:F;<

3 3 3 3

3 3 3 3

.F @= $ 8JB<; `$J K?< =@IJK JPD9FC a 8E; ?<8I; `P<Ja K?<E 8JB<;`$J K?< J<:FE; JPD9FC a 8E; ?<8I; `EFa K?<E 8JB<; `$J K?< K?@I;JPD9FCa8E;?<8I;`EFa$NFLC;BEFNK?8K3N8J@EJK8K<

)FN JLGGFJ< K?8K K?< JPJK<D 4 ?8J =FLI GFJJ@9C< JK8K<J N@K?K?<=FCCFN@E>GIF989@C@K@<J

4hni

4hni

4hni

4hni

/?<E K?< <EKIFGP F= 4 NFLC; 9< 9@KJ D<8E@E> K?8K N< :8E=@E;FLK@KJM8CL<9P8JB@E>P<JeFIeEFHL<JK@FEJ

2?8K ;F<J @K D<8E KF K8CB 89FLK 8JB@E> FE< 8E; K?I<<e=FLIK?JF= 8 HL<JK@FE $D8>@E< K?8K N< ;<J@>E8K< K?< JK8K<J F= 4 LJ@E> K?<=FCCFN@E>:F;<

4 4 4 4

http://lesswrong.com/lw/o1/entropy_and_short_codes/ +8><b2?<I<KFI8NK?<FLE;8IPc

!@IJK PFL 8JB `$J K?< =@IJK JPD9FC a $= K?< 8EJN<I @J `P<Ja PFLcI< ;FE< 4 @J @E JK8K< /?@J ?8GG<EJ ?8C= K?< K@D< JF n F= K?<K@D<@KK8B<JP<JeFIeEFHL<JK@FEKF=@E;FLK4cJJK8K<

.LGGFJ< K?8K @EJK<8; K?< 8EJN KNF P<JeFIeEF HL<JK@FEJ JF n F= K?<K@D<@KK8B<JHL<JK@FEJKF;@J:FM<I4cJJK8K<

$= K?< 8EJN<I @J `)Fa KN@:< @E 8 IFN PFL 8JB `$J K?< K?@I; JPDe9FC a $= `P<Ja PFLcI< ;FE< 8E; 4 @J @E JK8K< @= `EFa PFLcI< ;FE<8E; 4 @J @E JK8K< /?< F= K?< K@D< K?8K 4 @J @E JK8K< @K K8B<JK?I<< HL<JK@FEJ 8E; K?< F= K?< K@D< K?8K 4 @J @E JK8K< @K K8B<J

K?I<<HL<JK@FEJ

hihihihi

/?< ><E<I8C =FIDLC8 =FI K?< <EKIFGP F= 8 JPJK<D . @J K?< JLDFM<I8CC.@F=eGh.@ iCF> hGh.@ ii

!FI <O8DGC< K?< CF> h98J< i F= @J e .F eh ei @JK?< :FEKI@9LK@FE F= JK8K< . KF K?< KFK8C <EKIFGP F= K?< K@D< N<?8M<KF8JBHL<JK@FEJ

4FL :8EcK 8CN8PJ ;<M@J< 8 G<I=<:K :F;< =FI 8 JPJK<D 9LK @= PFL?8M< KF K<CC JFD<FE< K?< JK8K< F= 8I9@KI8I@CP D8EP :FG@<J F= . @E8 J@E>C< D<JJ8>< PFL :8E ><K 8I9@KI8I@CP :CFJ< KF 8 G<I=<:K :F;<h"FF>C<`8I@K?D<K@::F;@E>a=FI8J@DGC<D<K?F;i

)FN PFL D@>?K 8JB `2?P EFK LJ< K?< :F;< =FI 4 @EJK<8;F= 2FLC;EcKK?8KC<KLJKI8EJD@KD<JJ8><JDFI<HL@:BCPa

LK @= PFL LJ< K?< :F;< =FI 4 K?<E N?<E JFD<FE< 8EJN<IJ`4<Ja KF K?< HL<JK@FE `$J K?< =@IJK JPD9FC a PFL NFEcK BEFN P<K

N?<K?<K?< :F;< K?@J N8P K?< N?FC< JPJK<D =8CCJ 8G8IKg9<:8LJ< @= PFL ?<8I`a PFL ;FEcK BEFN @= @K D<8EJ `4 =FCCFN<; 9P 4a FI `4 =FCeCFN<;9P4a

/?<DFI8C@JK?8K short words are a conserved resource.

/?< B 8 >FF; :F;<g8 :F;< K?8K KI8EJD@KJ D<Je

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http://lesswrong.com/lw/o9/words_as_mental_paintbrush_handles/

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`GGC<a @JEcK ALJK 8 J<HL<E:< F= KNF JPCC89C<J FI =@M< C<KK<IJ/?8KcJ8J?8;FN /?8KcJK?<K@GF=K?<K@><IcJK8@C

2FI;J FI I8K?<J @E PFLI FNE D@E; '@K<I8CCP ;I8N @= PFL <DGCFP :FE:<GKJ KF D8B< 8 G@:KLI< @E PFLI M@JL8C :FIeK<O E; 9P K?< LJ< F= J?8I<; C89<CJ PFL :8E I<8:? @EKF JFD<FE<<CJ<cJ D@E; 8E; >I8JG K?<@I G8@EK9ILJ?<J KF ;I8N G@:KLI<J @E their D@E;JgJB<K:?8C@KKC<>I<<E;F>@EK?<@IM@JL8C:FIK<O

LK ;FEcK K?@EB K?8K 9<:8LJ< PFL J<E; JPCC89C<J K?IFL>? K?< 8@IFI C<KK<IJ K?IFL>? K?< $EK<IE<K @K @J K?< JPCC89C<J FI K?< C<KK<IJ K?8K;I8N G@:KLI<J @E K?< M@JL8C :FIK<O /?8K K8B<J JFD< :FDGC<O @EeJKIL:K@FEJ K?8K NFLC;EcK =@K @E K?< J<HL<E:< F= C<KK<IJ `GGC<a @J 9PK<J 8E; ;I8N@E> 8 G@:KLI< F= 8E 8GGC< =IFD J:I8K:? NFLC; K8B<DFI<;8K8K?8EK?8K

-%&6+-!,'/'*+

`GGC<a @J D<I<CP K?< K8> 8KK8:?<; KF K?< KIL< 8E; NFI;C<JJ apple:FE:<GK N?@:? :8E G8@EK 8 G@:KLI< @E PFLI M@JL8C :FIK<O FI :FCC@;<

N@K? `:?<<J<a FI I<:F>E@Q< 8E 8GGC< N?<E PFL J<< FE< FI K8JK< @KJ

8I:?<KPG< @E 8GGC< G@< D8P9< <M<E J<E; FLK K?< DFKFI 9<?8M@FI =FI<8K@E>8E8GGC<_

E; @KcJ EFK 8J J@DGC< 8J ALJK :8CC@E> LG 8 G@:KLI< =IFD D<DFIP*I ?FN NFLC; PFL 9< 89C< KF M@JL8C@Q< :FD9@E8K@FEJ C@B< 8 `KI@8Ee

>LC8I C@>?K9LC9ag@DGFJ@E> KI@8E>C<E<JJ FE C@>?K9LC9J B<<G@E> K?<<JJ<E:<F=9FK?<M<E@=PFLcM<E<M<IJ<<EJL:?8K?@E>@EPFLIC@=<

FEcK D8B< K?< D@JK8B< K?< 9<?8M@FI@JKJ D8;< /?<I<cJ =8IDFI< KF JG<<:? K?8E JFLE; @E 8@I /?< C89<CJ 8I< ALJK GF@EKe<IJgaCFFB @E D<DFIP 8I<8 a .FFE<I FI C8K<I N?<E PFLcI<

?8E;<; 8 GF@EK<I @K :FD<J K@D< KF ;<I<=<I<E:< @K 8E; 8:KL8CCP CFFB@ED<DFIP8I<8

2?8K;F<J8NFI;GF@EKKF

/'*++%&,$(!&,*-+&$+

27. Variable Question Fallacies

Followup to 2FI;J8J(<EK8C+8@EK9ILJ?#8E;C<J

C9<IK `M<IPK@D<$cM<C@JK<E<;KF8KI<<=8CC@KD8;<8 JFLE;JF$cCC>L<JJK?8KFK?<IKI<<J=8CC@E>8CJFD8B<JFLE;J $;FEcK9<C@<M<K?<NFIC;:?8E><J8IFLE;N?<E$cDEFKCFFB@E>a8IIP `28@K8D@ELK< $=EFFE<?<8IJ@K?FN:8E@K9<8JFLE;a

2?@C< NI@K@E> K?< ;@8CF>L< F= C9<IK 8E; 8IIP @E K?<@I ;@JGLK<

FM KI<< @E 8 ;<J<IK<; =FI<JK D8B<J 8 JFLE;$ JFD<K@D<J =FLE; DPJ<C= CFJ@E> <DG8K?P N@K? DP :?8I8:K<IJ $

NFLC; JK8IK KF CFJ< K?< >LK =<<C F= N?P anyone NFLC; <ML< C@B<K?8K<M<EK?FL>?$c;J<<E@K?8GG<ED8EPK@D<J

*E K?<J< F::8J@FEJ $ NFLC; I<G<8K KF DPJ<C= `@K? KI<< D8B<J 8 JFLE; FI @K ;F<J EFKa KF I<JKFI< DP 9FIIFN<; J<EJ<F=@E;@>E8K@FE

h+ FI S+i @J EFK 8CN8PJ 8 I<C@89C< ?<LI@JK@: @= PFL JL9JK@KLK< 8Ie

9@KI8IP E>C@J? J<EK<E:<J =FI + `/?@J J<EK<E:< @J =8CJ<a :8EEFK 9<:FEJ@JK<EKCP M@<N<; 8J KIL< FI =8CJ< E; K?<E K?<I<cJ K?< FC; :C8JeJ@:`#8M<PFLJKFGG<;9<8K@E>PFLIN@=<a

)FN @= PFL 8I< 8 D8K?<D8K@:@8E 8E; FE< N?F 9<C@<M<J @E :C8JeJ@:8C hI8K?@: K?<I< 8I< N8PJ KF :FEK@EL<@EJ@JK@E> K?8K h+ FI S+i @J 8 K?<FI<D =FI <O8DGC< J8P@E> K?8K `/?@JJ<EK<E:<@J=8CJ<a@JEFK8J<EK<E:<

LK JL:? I<JFCLK@FEJ 8I< JL9KC< N?@:? JL==@:<J KF ;<DFEJKI8K<8 E<<; =FI JL9KC<KP 4FL :8EEFK ALJK 9LCC 8?<8; FE <M<IP F::8J@FE

N@K?`@K?<I@K;F<JFI@K;F<JEcKa

.F;F<JK?<=8CC@E>KI<<D8B<8JFLE;FIEFKFI_

.LI<CP 3 FI @K ;F<J EFK 2<CC D8P9< if @KcJ really K?<J8D< 3 K?< J8D< 8E; K?< J8D< 8E; $= 3 <M8CL8K<J KF FEJFD< F::8J@FEJ 8E; FE 8EFK?E8K@FE D8P 9< D@JeGC8:<;

http://lesswrong.com/lw/oc/variable_question_fallacies/

+8><b2FI;J8J(<EK8C+8@EK9ILJ?#8E;C<Jc +8><b@JGLK@E><=@E@K@FEJc

/F <M<E 9<>@E :C8@D@E> K?8K h+ FI S+i FL>?K KF 9< 8 E<:<JJ8IP KILK? K?< JPD9FC + DLJK JK8E; =FI exactly K?< J8D< K?@E> @E 9FK??8CM<J F= K?< ;@C<DD8 `@K? G8I8;FO@:8C 89FLK K?< KI<< D8B@E> 8E C9<IKJFLE; 9LK EFK 8 8IeIPJFLE;

h/?< @;@FD @J JFD<K?@E> $ G@:B<; LG @E DP ;8PJ =FI8MF@;@E> E8D<JG8:< :FCC@J@FEJ $= PFLcM< >FK KNF ;@==<I<EK G8:B8><JK?8K ;<=@E< 8 :C8JJ .FLE; PFL :8E NI@K< +8:B8><.FLE; KF JG<:@=P

N?@:? .FLE; PFL D<8E /?< @;@FD @J EFK N@;<CP BEFNE $ K?@EB N?@:?@J8G@KP9<:8LJ<$F=K<EN@J?$:FLC;LJ<@K@ENI@K@E>i

/?< M8I@89@C@KP D8P 9< JL9KC< C9<IK 8E; 8IIP D8P :8I<=LCCP

M<I@=P K?8K @K @J K?< J8D< KI<< @E K?< J8D< =FI<JK 8E; K?< J8D<F::8J@FE F= =8CC@E> ALJK KF <EJLI< K?8K K?I<<D<EK 89FLK <O8:KCP K?< J8D< <M<EK E; K?<E =FI><KKF :?<:B K?8K K? K?@J <M<EK 8>8@EJK <O8:KCP K?< J8D<:FE:<GK

/?@EB 89FLK K?< >IF:<IP JKFI< K?8K PFL M@J@K DFJK F=K<E $J @KFE K?< C<=K J@;< F= K?< JKI<<K FI K?< I@>?K LK F= :FLIJ< K?<I< @J EF`the C<=K J@;<a F= K?< JKI<<K FECP your C<=K J@;< 8J PFL KI8M<C 8CFE> @K

=IFD JFD< G8IK@:LC8I ;@I<:K@FE (8EP F= K?< NFI;J N< LJ< 8I< I<8CeCP=LE:K@FEJF=@DGC@:@KM8I@89C<JJLGGC@<;9P:FEK<OK

$KcJ 8:KL8CCP FE< ?<:B F= 8 G8@E I<HL@I@E> FE< ?<:B F= 8 CFK F= NFIB KF ?8E;C< K?@J B@E; F= GIF9C<D @E 8E IK@=@:@8C $EK<CC@><E:<GIF>I8D @EK<E;<; KF G8IJ< C8E>L8><gK?< G?<EFD<EFE >F@E> 9P K?<E8D<F=`JG<8B<I;<@O@Ja

`(8IK@E KFC; F9 K?< 9L@C;@E> N8J FE ?@J C<=Ka LK `C<=Ka @J8 =LE:K@FEeNFI; K?8K <M8CL8K<J N@K? 8 JG<8B<Ie;<G<E;<EK M8I@89C<@EM@J@9CP >I899<; =IFD K?< JLIIFLE;@E> :FEK<OK 2?FJ< `C<=Ka @J

D<8EKF9cJFI(8IK@EcJ/?< M8I@89C<J @E 8 M8I@89C< HL<JK@FE =8CC8:P F=K<E 8I<EcK E<8KCP C8e

9<C<;g@KcJEFK8JJ@DGC<8J`.8P;FPFLK?@EB5<HL8CJa

$= 8 E8D<JG8:< :FCC@J@FE @EKIF;L:<J KNF ;@==<I<EK :FE:<GKJ K?8KCFFB C@B< `K?< J8D< :FE:<GKa 9<:8LJ< K?<b/89FF4FLI2FI;Jc +8><b!8CC8:@<JF=FDGI<JJ@FEc

.*!$)-+,!'&$$!+

K?< J8D< =LE:K@FE <M8CL8K<J @E ;@==<I<EK :FEK<OKJgK?<E I<8C@KP @KeJ<C= 9<:FD<J GIFK<8E :?8E><89C< K C<8JK K?8KcJ N?8K K?< 8C>FeI@K?D =<<CJ C@B< =IFD @EJ@;< 4FLI D@E;cJ <P< J<<J K?< D8G EFK K?<

K<II@KFIP;@I<:KCP$= PFL ?8M< 8 HL<JK@FE N@K? 8 ?@;;<E M8I@89C< K?8K <M8CL8K<J KF

;@==<I<EK <OGI<JJ@FEJ @E ;@==<I<EK :FEK<OKJ @K feels like I<8C@KP @KJ<C= @J LEJK89C<gN?8K PFLI D@E;cJ <P< J<<J J?@=KJ 8IFLE; ;<G<E;@E> FE

N?<I<@KCFFBJ

/?@J F=K<E :FE=LJ<J LE;I8;L8K<J h8E; GFJKDF;<IE@JK GIF=<JeJFIJi N?F ;@J:FMFJ? b/?< .LE >F<J 8IFLE; K?< 8IK?c @J KIL< =FI #LE>8 #LEK8K?<IF<J 8IFLE;K?< 8IK?c @J =8CJ< /?<I< @J EF =@O<; KILK?a /?< ;<:FEJKIL:K@FE F= K?@JJFG?FDFI@:E@KN@KK<IP@JC<=K8J8E<O<I:@J<KFK?<I<8; `$= 3 @J FE JFD<F::8J@FEJ 8E; FE 8EFK?<I K?< J<EK<E:< b 3c D8P ?8M< EF=@O<; KILK?eM8CL<a /?<I< @J EFK one J<EK<E:< N@K? 8 variable KILK?e

M8CL< ` 3a has no KILK?eM8CL< $K @J EFK 8 proposition, EFK P<KEFK 8J D8K?<D8K@:@8EJ ;<=@E< GIFGFJ@K@FEeE<JJ 8EP DFI< K?8E `

a @J 8 GIFGFJ@K@FE FI `!I<; ALDG<; FMI8DD8K@:8C J<EeK<E:<

LK K?@J =8CC8:P K<E;J KF JE<8B @E <M<E N?<E PFL 8CC<><;CP BEFN 9<KK<I9<:8LJ<N<CCK?8KcJ?FNK?< 8C>FI@K?D=<<CJ=IFD@EJ@;<

+8><b#FNEC>FI@K?D!<<CJ!IFD$EJ@;<c +8><b#FNEC>FI@K?D!<<CJ!IFD$EJ@;<c

-%&6+-!,'/'*+

28. 37 Ways That Words Can Be Wrong

Followup to: %LJK 89FLK <M<IP GFJK @E !<9IL8IP 8E; JFD< @E

(8I:?.FD< I<8;FI@<J 8E #8M< )<>8K@M< .@;<==<:KJ*E4FLIF>E@K@FEa

LK FE< F= K?< GI@D8IP C<JJFEJ F= K?@J >@>8EK@: C@JK @J K?8K J8P@E> `/?<I<cJ EF N8P DP :?F@:< F= 3 :8E 9< bNIFE>ca @J E<8ICP 8CN8PJ 8E<IIFI @E GI8:K@:< N?8K<M

M<E N?<E @KcJ K?<FI<K@:8CCP @DGFJJ@9C< KF 9< NIFE> PFL :8E JK@CC9< NIFE> /?<I< @J E<M PFL;F /?8KcJC@=<

<J@;<J $ :8E ;<=@E< K?< NFI; `NIFE>a KF D<8E 8EPK?@E> $ C@B<e@KcJEFKC@B<8NFI;:8E9< wrong.

+<IJFE8CCP $ K?@EB @K HL@K< ALJK@=@<; KF LJ< K?< NFI; `NIFE>a N?<E

A word fails to connect to reality in the first place. $J.F:I8K<J8 =I8DJK><I i

Your argument, if it worked, could coerce reality to go a different way by choosing a different word definition. .F:I8K<J@J8 ?LD8E8E;?LD8EJ9P;<=@E@K@FE8I<DFIK8C .F@=PFL;<=@E<;?LD8EJKFEFK9<DFIK8CNFLC;.F:I8K<JC@M<=FI<M<I h/?<+8I89C<F=#<DCF:Bi

You try to establish any sort of empirical proposition as being true“by definition”. .F:I8K<J@J8?LD8E8E;?LD8EJ9P ;<=@E@K@FE8I<DFIK8C .F@J@K8 logical truth @=N<

<DG@I@:8CCPGI<;@:KK?8K.F:I8K<JJ?FLC;B<<CFM<I@=?<;I@EBJ?<DCF:B $KJ<<DJC@B<K?<I<8I<CF>@:8CCPGFJJ@9C<EFEeJ<C=e:FEKI8;@:KFIPNFIC;JN?<I<.F:I8K<J;F<JEcKB<<CFM<IeN?<I<?<cJ@DDLE<KF?<DCF:B9P8HL@IBF= 9@F:?<D@JKIPJ8P 'F>@:8CKILK?J8I<KIL<@E8CCGFJJ@9C<

NFIC;J8E;JFE<M<IK<CCPFL which GFJJ@9C<NFIC;PFLC@M<

http://lesswrong.com/lw/od/37_ways_that_words_can_be_wrong/

+8><b/?<+8I89C<F=K?<8>><Ic +8><b/?<+8I89C<F=#<DCF:Bc

@Ee8E;8EPK?@E>PFL:8E<JK89C@J?`9P;<=@E@K@FEa@J8 CF>@:8CKILK? h/?<+8I89C<F=#<DCF:Bi

You unconsciously slap the conventional label on something,

without actually using the verbal definition you just gave. 4FLBEFNG<I=<:KCPN<CCK?8KF9@J`?LD8Ea<M<EK?FL>?FE PFLI;<=@E@K@FEPFL:8EE<M<I:8CCF9`?LD8EaN@K?FLK=@IJKF9J<IM@E>?@DKF9<DFIK8C h/?<+8I89C<F= #<DCF:Bi

The act of labeling something with a word, disguises achallengable inductive inference you are making. $=K?<C8JK<>>eJ?8G<;F9A<:KJ;I8NE?8M<9<<E9CL<8E;K?<C8JK:L9<J;I8NE?8M<9<<EI<;@K@J8D8KK<IF=@E;L:K@FEKF

J8PK?@JILC<N@CC?FC;@EK?<=LKLI< LK@=PFL:8CCK?<9CL<<>>J`9C<>>Ja8E;K?<I<;:L9<J`IL9<JaPFLD8P I<8:?@EKFK?<98II<C=<<C8E<>>J?8G<8E;K?@EB`*?8 9C<>>a h2FI;J8J#@;;<E$E=<I<E:<J i

You try to define a word using words, in turn defined with ever- more-abstract words, without being able to point to an example.`2?8K@JI<;a `-<;@J8:FCFIa `2?8KcJ8:FCFIa `$KcJ8 GIFG<IKPF=8K?@E>a `2?8KcJ8K?@E> 2?8KcJ8 GIFG<IKPa $KE<M<IF::LIJKFPFLKFGF@EKKF8JKFGJ@>E8E;8E8GGC< hOK<EJ@FEJ8E;$EK<EJ@FEJ i

The extension doesn’t match the intension. 2<8I<EcK:FEJ:@FLJCP8N8I<F=FLI@;<EK@=@:8K@FEF=8I<;C@>?K@EK?<JBP8J`(8IJaN?@:?N@CCGIF989CP?8GG<EI<>8I;C<JJF=

PFLI8KK<DGKKF;<=@E<`(8IJa8J`/?<"F;F=28IahOK<EJ@FEJ8E;$EK<EJ@FEJ i

Your verbal definition doesn’t capture more than a tiny fractionof the category’s shared characteristics, but you try to reason as if

it does. 2?<EK?<G?@CFJFG?<IJF=+C8KFcJ:8;<DP :C8@D<;K?8KK?<9<JK;<=@E@K@FEF=8?LD8EN8J8 `=<8K?<IC<JJ9@G<;a@F><E<JK?<PE@:@JJ8@;KF?8M<<O?@9@K<;8GCL:B<;:?@:B<E8E;;<:C8I<;`#<I<@J+C8KFcJ(8Ea /?<+C8KFE@JKJGIFDGKCP:?8E><;K?<@I;<=@E@K@FE

+8><b/?<+8I89C<F=#<DCF:Bc +8><b/?<+8I89C<F=#<DCF:Bc +8><b2FI;J8J#@;;<E$E=<I<E:<Jc

+8><bOK<EJ@FEJ8E;$EK<EJ@FEJc +8><bOK<EJ@FEJ8E;$EK<EJ@FEJc

-%&6+-!,'/'*+

KF`8=<8K?<IC<JJ9@G<;N@K?9IF8;E8@CJa h.@D@C8I@KP CLJK<IJ i

You try to treat category membership as all-or-nothing, ignoring

the existence of more and less typical subclusters. L:BJ8E;G<E>L@EJ8I<C<JJKPG@:8C9@I;JK?8EIF9@EJ8E;G@><FEJ$EK<I<JK@E>CP89<KN<<Ee>IFLGJ<OG<I@D<EKJ?FN<;K?8KJL9A<:KJK?FL>?K8;@J<8J<N8JDFI<C@B<CPKFJGI<8;=IFDIF9@EJKF;L:BJFE8E@JC8E;K?8E=IFD;L:BJKFIF9@EJh/PG@:8C@KP8E;JPDD<KI@:8C.@D@C8I@KP i

A verbal definition works well enough in practice to point out theintended cluster of similar things, but you nitpick exceptions. )FK<M<IP?LD8E?8JK<E=@E><IJFIN<8IJ:CFK?<JFILJ<J

C8E>L8><9LK@=PFLCFFB=FI8E<DG@I@:8C:CLJK<IF=K?@E>J N?@:?J?8I<K?<J<:?8I8:K<I@JK@:JPFLcCC><K<EFL>?@E=FID8K@FEK?8KK?<F::8J@FE8CE@E<e=@E><I<;?LD8E

NFEcK=FFCPFL h/?<CLJK<I.KIL:KLI<F=/?@E>JG8:<i You ask whether something “is” or “is not” a category member but

can’t name the question you really want answered. 2?8K@J8 `D8Ea $J8IE<PK?<89PFP8`D8Ea /?<`:FII<:Ka8EJN<ID8P;<G<E;:FEJ@;<I89CPFEN?<K?<IK?<HL<IP

PFL really N8EK8EJN<I<;@J`2FLC;?<DCF:B9<8>FF;K?@E>KF=<<;8IE<PaFI`2@CC8IE<PD8B<8>FF;?LJ98E;a h@J>L@J<;,L<I@<J i

You treat intuitively perceived hierarchical categories like theonly correct way to parse the world, without realizing that other forms of statistical inference are possible even though your brain doesn’t use them. $KcJDL:?<8J@>aFI`IL9<aK?8E for a humanKFEFK@:<K?8KI<;F9A<:KJE<MCFN@EK?<;8IB9LKI<;

=LII<;F9A<:KJ?8M<8CCK?<FK?<I:?8I8:K<I@JK@:JF=9C<>>J*K?<IJK8K@JK@:8C8C>FI@K?DJNFIB;@==<I<EKCP h)<LI8C8K<>FI@<J i

You talk about categories as if they are manna fallen from the Platonic Realm, rather than inferences implemented in a real brain. /?<8E:@<EKG?@CFJFG?<IJJ8@;`.F:I8K<J@J8D8Ea

+8><b.@D@C8I@KPCLJK<IJc +8><b/PG@:8C@KP8E;JPDD<KI@:8C.@D@C8I@KPc +8><b/?<CLJK<I.KIL:KLI<F=/?@E>JG8:<c

+8><b@J>L@J<;,L<I@<Jc +8><b)<LI8C8K<>FI@<Jc

/1+,,/'*+&/*'&

EFK`(P9I8@EG<I:<GKL8CCP:C8JJ@=@<J.F:I8K<J8J8D8K:?8>8@EJKK?<b?LD8Ec:FE:<GKa h#FNEC>FI@K?D!<<CJ!IFD$EJ@;>eJ?8G<;=LII<;=C<O@9C<FG8HL<CLD@E<J:<EK8E;G8CC8;@LDe:FEK8@E@E>N?8KcJ left KF8JB9P8I>L@E>`$J@K8 9C<>>a LK@=PFLI9I8@EcJ:8K<>FI@Q@E>E<LI8CE<KNFIB:FEK8@EJ8hD<K8G?FI@:8Ci:<EKI8CLE@K:FII<JGFE;@E>KFK?<@E=<I<E:<F=9C<>>eE<JJ@KD8PJK@CC feel C@B<K?<I<cJ8 C<=KFM<IHL<JK@FE h#FNEC>FI@K?D!<<CJ!IFD

$EJ@;@E8 ;<J<IK<;=FI<JKD8B<J8`JFLE;aPFL8JB<;K?<KNFJFFEeKFe9<8I>L<IJN?<K?<IK?<PK?FL>?K8 JFLE;aJ?FLC;9<;<=@E<;8J`8:FLJK@:M@9I8K@FEJaFI`8L;@KFIP<OG<I@<E:<JaK?<Pc;GIF989CPK<CCPFLKF=C@G8:F@E *ECP8=K<IK?<8I>LD<EKJK8IKJ;F<JK?<;<=@E@K@FEF=8NFI;9<:FD<GFC@K@:8CCP:?8I><; h@JGLK@E><=@E@K@FEJ i

You think a word has a meaning, as a property of the word itself; rather than there being a label that your brain associates to a particular concept. 2?<EJFD<FE<J?FLKJ`4@B<J K@><Ia<MFCLK@FENFLC;EFK=8MFI8EFI>8E@JDK?8KK?@EBJ`#D_$?8M<ALJK?<8I;K?<JPCC89C<Jb/@<c8E;b"IIcN?@:?DP=<CCFNKI@9<D<D9<IJ8JJF:@8K<N@K?K?<@I@EK<IE8C8E8CF>L<JF=DPFNE tiger :FE:<GK8E;N?@:? aiiieeee

-0)#-0)#"0'+a .FK?<9I8@EK8B<J8 J?FIK:LK8E;@KJ<<DJK?8KK?<D<8E@E>F=K@><IE<JJ@J8 GIFG<IKPF=K?<C89<C@KJ<C= +<FGC<8I>L<89FLKK?< correct meaning F=8C89<CC@B<`JFLE;ah!<<CK?<(<8E@E> i

You argue over the meanings of a word, even after all sidesunderstand perfectly well what the other sides are trying to say./?<?LD8E89@C@KPKF8JJF:@8K<C89<CJKF:FE:<GKJ@J8KFFC

+8><b#FNEC>FI@K?D!<<CJ!IFD$EJ@;<c +8><b#FNEC>FI@K?D!<<CJ!IFD$EJ@;<c

+8><b@JGLK@E><=@E@K@FEJc +8><b!<<CK?<(<8E@E>c

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=FI:FDDLE@:8K@FE 2?<EG<FGC< want KF:FDDLE@:8K< N<cI<?8I;KFJKFG@=N<?8M<EF:FDDFEC8E>L8><N<cCC;I8NG@:KLI<J@EJ8E; 2?<EPFL<8:?LE;<IJK8E;N?8K@J

@EK?<FK?<IcJD@E;PFL8I< done. h/?LD<EK!IFDFDDFE0J8><EFKC<>@JC8KFIJF=C8E>L8>< $=K?<:FDDFE;<=@E@K@FE:FEK8@EJ8GIF9C<De@=`(8IJa@J;<=@E<;8JK?<"F;F=28IFI8 `;FCG?@Ea@J;<=@E<;8J8B@E;F==@J?FI`)<>IF<Ja8I<;<=@E<;8J8J<G8I8K<:8K<>FIP=IFD?LD8EJK?<;@:K@FE8IPN@CCI<=C<:KK?<JK8E;8I;D@JK8B< h/?LD<EK!IFDFDDFE0J8>@FEaFIN?8K<MLD<EKh/?LD<EK!IFDFDDFE0J8><CJN@K?FLK?8E;C< h/?LD<EK!IFDFDDFE0J8>< i

You use complex renamings to create the illusion of inference. $J8 `?LD8Ea;<=@E<;8J8`DFIK8C=<8K?<IC<JJ9@G<;a /?<E

NI@K< `CCjDFIK8C=<8K?<IC<JJ9@G<;Jk8I<DFIK8C.F:I8K<J@J8jDFIK8C=<8K?<IC<JJ9@G<;kK?<I<=FI<.F:I8K<J@JDFIK8Ca 'FFBJC<JJ@DGI<JJ@M<K?8KN8P;F<JEcK@K

hDGKP'89<CJ i You get into arguments that you could avoid if you just didn’t use

the word. $=C9<IK8E;8IIP8I<EcK8CCFN<;KFLJ<K?< NFI;`JFLE;aK?<EC9<IKN@CC?8M<KFJ8P`KI<<=8CC@E> @E8;<J<IK<;=FI<JK><E<I8K<J8:FLJK@:M@9I8K@FEJa8E;8IIPN@CCJ8P`KI<<=8CC@E>@E8;<J<IK<;=FI<JK><E<I8K<J

+8><b/?LD<EK=IFDFDDFE0J8><c +8><b/?LD<EK=IFDFDDFE0J8><c +8><b/?LD<EK=IFDFDDFE0J8><c

+8><b/?LD<EK=IFDFDDFE0J8><c +8><bDGKP'89<CJc

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EF8L;@KFIP<OG<I@<E:<Ja 2?<E8NFI;GFJ<J8GIF9C<DK?<J@DGC<JKJFCLK@FE@JKF<C@D@E8K<K?<NFI;8E;@KJJPEFEPDJ h/89FF4FLI2FI;J i

The existence of a neat little word prevents you from seeing the details of the thing you’re trying to think about. 2?8K8:KL8CCP >F<JFE@EJ:?FFCJFE:<PFLJKFG:8CC@E>@K`<;L:8K@FEa2?8KcJ8;<>I<<FE:<PFLJKFG:8CC@E>@K8 ;<>I<<a $=8 :F@EC8E;J`?<8;JaN?8KcJ@KJI8;@8CFI@<EK8K@FE 2?8K@J`KILK?a@=PFL:8EcKJ8P`8::LI8K<aFI :FII<:KaFIÌ<GI<J<EKaFIÌ<=C<:KaFI`J<D8EK@:aFI`9<C@<M<aFI`BEFNC<;><aFI`D8GaFIÌ<8CaFI8EPFK?<IJ@DGC<K<IDh-<GC8:<K?<.PD9FCN@K?K?<.L9JK8E:< i

You have only one word, but there are two or more different things-in-reality, so that all the facts about them get dumped into a single undifferentiated mental bucket. $KcJG8IKF=8 ;<K<:K@M<cJFI;@E8IPNFIBKFF9J<IM<K?8K8IFCNFI<I<;C8JKE@>?KFIK?8KJ?<?8J9C8:B?8@I8E;@KcJG8IKF=8 ;<K<:K@M<cJFI;@E8IPNFIBKFNFE;<I@=D8P9<8IFC;P<J?<I?8@I LK@KK8B<J8JL9KC<I;<K<:K@M<KFNFE;<I@= K?<I<8I<KNF8IFCJJFK?8KK?<8IFCN?FNFI<I<;@JEFKK?<J8D<8JK?<8IFCN?F?8;9C8:B?8@I h!8CC8:@<JF=FDGI<JJ@FE i

You see patterns where none exist, harvesting other characteristics from your definitions even when there is no similarity along that dimension. $E%8G8E@K@JK?FL>?KK?8KG<FGC<F=9CFF;KPG<8I<<8IE<JK8E;:I<8K@M<9CFF;KPG<J8I<N@C;8E;:?<<I=LC9CFF;KPG<*J8I<8>I<<89C<8E;JF:@89C<8E;9CFF;KPG<J8I<:FFC8E;:FEKIFCC<;h8K<>FI@Q@E>#8JFEJ<HL<E:<J i

You try to sneak in the connotations of a word, by arguing from a definition that doesn’t include the connotations. `N@>>@Ea@J;<=@E<;@EK?<;@:K@FE8IP8J8G<IJFEN@K?>I<<E<P<J8E;9C8:B?8@I /?<NFI;`N@>>@Ea8CJF:8II@<JK?<:FEEFK8K@FEF=JFD<FE<N?F:FDD@KJ:I@D<J8E;C8LE:?<J:LK<989PJHL@II<CJ9LKK?8KG8IK@JEcK@EK?<;@:K@FE8IP .FPFLGF@EKKFJFD<FE<8E;J8P `"I<<E

+8><b/89FF4FLI2FI;Jc +8><b-<GC8:<K?<.PD9FCN@K?K?<.L9JK8E:<c

+8><b!8CC8:@<JF=FDGI<JJ@FEc +8><b8K<>FI@Q@E>#8JFEJ<HL<E:<Jc

-%&6+-!,'/'*+

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You claim “X, by definition, is a Y!” On such occasions you’re almost certainly trying to sneak in a connotation of Y that wasn’t in your given definition. 4FL;<=@E<`?LD8Ea8J8 `=<8K?<IC<JJ9@G<;a8E;[email protected]:I8K<J8E;J8P`)F=<8K?<IJeKNFC<>Je?<DLJK9<?LD8Ea LKN?8KPFL really :8I<89FLK@JJFD<K?@E><CJ<C@B<DFIK8C@KP $=N?8K N8J@E;@JGLK<N8J.F:I8K<JcJELD9<IF=C<>JK?<FK?<I=<CCFNNFLC;ALJKI<GCP`2?8;;8P8D<8E.F:I8K<JcJ>FKKNFC<>J /?8KcJN?8KN<cI<8I>L@E>89FLK@EK?<=@IJK

GC8:<a hI>L@E>`P<=@E@K@FEa i You claim “Ps, by definition, are Qs!” $=PFLJ<<.F:I8K<JFLK

@EK?<=@<C;N@K?JFD<9@FCF>@JKJ>8K?<I@E>?<I9JK?8KD@>?K:FE=<II<J@JK8E:<KF?<DCF:BK?<I<cJEFGF@EK@E8I>L@E>`(<E9P;<=@E@K@FE8I<DFIK8Ca /?<D8@EK@D<

PFL=<<CK?<E<<;KFK@>?K<EK?<M@J<9P@EJ@JK@E>K?8KJFD<K?@E>@JKIL<`9P;<=@E@K@FEa@JN?<EK?<I<cJFK?<I@E=FID8K@FEK?8K:8CCJK?<;<=8LCK@E=<I<E:<@EKF;FL9KhI>L@E>`P<=@E@K@FEa i

You try to establish membership in an empirical cluster “by definition”. 4FLNFLC;EcK=<<CK?<E<<;KFJ8P`#@E;L@JDby definition, @J8I<C@>@FEa9<:8LJ<N<CCF=:FLIJ<#@E;L@JD@J8I<C@>@FE $KcJEFKALJK8I<C@>@FE`9P ;<=@E@K@FEa@KcJC@B<8E actual I<C@>@FE K?<@JD;F<JEFKI<J<D9C<K?<:<EKI8CD<D9<IJF=K?<`I<C@>@FEa:CLJK<IJF@=@KN8JEcK=FIK?<=8:KK?8K8K?<@JD@J8I<C@>@FE by definition, PFLD@>?K>F8IFLE;K?@EB@E>K?8K8K?<@JD

wasn’t 8I<C@>@FE /?8KcJN?PPFLcM<>FKKF:ILJ?8CCFGGFJ@K@FE9PGF@EK@E>FLKK?8K`K?<@JD@J8I<C@>@FEa@JKIL< by definition9<:8LJ<@K@JEcKKIL<8EPFK?<IN8PhI>L@E>`P<=@E@K@FEa i

Your definition draws a boundary around things that don’t reallybelong together. 4FL:8E:C8@D@=PFLC@B<K?8KPFL8I< defining K?<NFI;`=@J?aKFI<=<IKFJ8CDFE>LGG@<JJ?8IBJ

+8><b.E<8B@E>@EFEEFK8K@FEJc +8><bI>L@E>`P<=@E@K@FEac

+8><bI>L@E>`P<=@E@K@FEac +8><bI>L@E>`P<=@E@K@FEac

/1+,,/'*+&/*'&

;FCG?@EJ8E;KIFLK9LKEFKA<CCP=@J?FI8C>8< 4FL:8E:C8@D@=PFLC@B<K?8KK?@J@JD<I<CP8C@JK8E;K?<I<@JEF

N8P8C@JK:8E9<`NIFE>a *IPFL:8EJKFGGC8P@E>E@KN@K

>8D<J8E;8;D@KK?8KPFLD8;<8D@JK8B<8E;K?8K;FCG?@EJ;FEcK9<CFE>FEK?<=@J?C@JK h2?<I<KFI8N K?<FLE;8IP i

You use a short word for something that you won’t need to describe often, or a long word for something you’ll need to describeoften. This can result in inefficient thinking, or even misapplications of Occam’s Razor, if your mind thinks that short sentences sound “simpler”. 2?@:?JFLE;JDFI<GC8LJ@9C<`"F;;@;8D@I8:C<aFI`JLG<IE8KLI8CLE@M<IJ<e:I<8K@E>

<EK@KPK<DGFI8I@CPJLJG<E;<;K?<C8NJF=G?PJ@:JahEKIFGP8E;.?FIKF;<J i

You draw your boundary around a volume of space where thereis no greater-than-usual density, meaning that the associated word does not correspond to any performable Bayesian inferences..@E:<>I<<Ee<P<;G<FGC<8I<EFKDFI<C@B<CPKF?8M<9C8:B?8@IFIM@:<M<IJ88E;K?<P;FEcKJ?8I<8EPFK?<I:?8I8:K<I@JK@:J@E:FDDFEN?P?8M<8NFI;=FI`N@>>@Eah(LKL8C$E=FID8K@FE8E;<EJ@KP@E/?@E>JG8:8NFI;KFI<=<IKF8CC?LD8EJ<O:<GK9C8:BG<FGC<J<<DJB@E;F=JLJG@:@FLJ $=PFL;FEcKGI<J<EKI<8JFEJKF;I8NK?8KG8IK@:LC8I9FLE;8IPKIP@E>KF:I<8K<8E`8I9@KI8IPaNFI;@EK?8KCF:8K@FE@JC@B<8 ;<K<:K@M<J8P@E> `2<CC$?8M<EcKK?<JC@>?K<JKJ?I<;F= JLGGFIKFE<N8PFIK?<FK?<I=FIN?F:FLC;cM<DLI;<I<;K?FJ<FIG?8EJ_9LK?8M<N<:FEJ@;<I<;%F?E,

2@==C<?<@D8J8JLJG<:Ka h.LG<I<OGFE<EK@8CFE:<GKJG8:<8E;.@DGC<2FI;J i You use categorization to make inferences about properties that

don’t have the appropriate empirical structure, namely,conditional independence given knowledge of the class, to be well- approximated by Naive Bayes. )FN8P8D$KIP@E>KF

+8><b2?<I<KFI8NK?<FLE;8IPc +8><bEKIFGP8E;.?FIKF;<Jc

+8><b(LKL8C$E=FID8K@FE8E;<EJ@KP@E/?@E>JG8:<c +8><b.LG<I<OGFE<EK@8CFE:<GKJG8:<8E;.@DGC<2FI;Jc

-%&6+-!,'/'*+

lesswrong sequences volume 1.0

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