NO KNOWThe man behind Naomi in Starbucks dropped his rabbit keyring, and she

passed it back to him. The following day, she saw a bus screech to a halt,

and heard a thud; the man from Starbucks was dead underneath it. She told

the police she’d spoken to him yesterday in Starbucks, and he had a rabbit

keyring. A few days later, she screamed as she saw the very same man in

Starbucks again! He explained that his twin brother had been killed by the

bus, adding “it must be confusing for people, as we both come to the same

Starbucks, but never at the same time – and we have the same keyring”

Did Naomi tell the Police the truth?

Source: The Pig that Wants to be Eaten (2005) No.63

TODAY’S LESSONToday we will …• Learn when a justified true belief is not knowledge

• Look at some examples of ‘lucky justified true beliefs’

Some important philosophers• Gettier

Important terminology• Necessary and sufficient conditions• Justification• No false lemmas

GETTIER:WHEN A JUSTIFIED TRUE BELIEF ISN’T KNOWLEDGE

http://www.youtube.com/watch?v=_ldGT2R-pJM 4.50 mins

SMITH AND JONESSmith and Jones go for a job interview. Smith totally messes

up the interview, and is sure he won’t get the job. Jones has

brought his ten lucky coins along to the interview with him.

Smith forms the belief: “the man who will get the job has 10

coins in his pocket”. To his surprise, Smith gets the job! He

then realises that he too has 10 coins in his pocket.

Smith had a justified true belief that the man with 10 coins

would get the job. Did he KNOW it?

Source: The Pig that Wants to be Eaten (2005) No.63

NO FALSE LEMMASPhilosophers use the term “no false lemmas” to mean that the conclusion

must not be inferred from a false premise / assumption.

With Smith and Jones, Smith arrived at his JTB from the intermediate

conclusion that Jones would get the job. His conclusion that ‘the man who

gets the job has 10 coins’ was based on a false lemma.

This is sometimes known as the NFL principle

So the justified true belief that the man who got the job had 10 coins, was based on a false lemma (false belief) – the NFL principle state that this is not knowledge

•JONES WILL GET THE JOB•JONES HAS 10 COINS•C- THE MAN WHO GETS THE JOB WILL HAVE 10 COINS

False lemma (false belief)

ACTIVITY – 25 MINUTESCreate your own Gettier-style example

in which someone has a j.t.b. which isn’t knowledge

Draw this out as a storyboard / cartoon

You may work alone or in pairs (in the

pair, both partners must contribute)

REMEMBER…• X forms a belief• X is justified in

believing it• The belief turns out to

be true• But something

happened to mean that the truth is unrelated to the justification

HOMEWORKGO THROUGH THE TEST AND MY COMMENTS, AND LOOK AT THE MARK SCHEMES ON P62, AND WRITE YOURSELF SOME TARGETS TO IMPROVE. EMAIL ME YOUR ANSWERSFOLLOW SOME OF THE LINKS ON MOODLE ON JTB AND DRAW A MIND MAP BASED ON YOUR RESEARCH

ACTIVITY – 15 MINUTESAre j.t.b. really necessary?

Read p.30-31 of your booklets and draw a mind

map to summarise why justification, truth, and

belief may not be necessary conditions of

knowledge