Download - Reliabilism
Reliabilism
Justification
I believe that there is a dog tied out in front of the UCen.– I didn’t see the dog on my way here– No one told me about it– I have no past experience with dogs being tied up
there at this time of morning.– I am just guessing.
But as a matter of fact, there is a dog there!
Justification
Do I know that there is a dog there?
No!
Justification
Knowledge requires more than just a true belief. You need:– Reasons– Evidence– Rational support– Etc.
Justification
Call a belief justified if it is believed on a good basis (good reasons, good evidence, rational grounds, etc.).
Our skeptical arguments so far have concerned knowledge, but they can be easily reformulated to show that we cannot have justification for our beliefs about the external world.
Skepticism about Justification
Skepticism about justification is arguably closer to the real issue than skepticism about knowledge.
Skepticism about Justification
Skepticism about Justification
The skeptic does not try to show that our beliefs are false or that we fail to believe what we think we do.
Rather, he tries to show that our reasons for believing what we do are not strong enough to amount to knowledge.
Skepticism about Justification
If this is right, then skepticism is even worse than one might think.
Not only do you not know anything about the external world, you don’t even have good reasons to believe it!
The Transmissibility Argument (Justification)1.I cannot be justified in believing that I am not
a BIV.2.My having hands entails that I am not a BIV. 3.If I justifiably believe p and that p entails q,
then I can be justified in believing q.4.So, if I justifiably believe that I have hands,
then I can be justified in believing that I am not a BIV.
5.I cannot be justified in believing that I have hands.
Skepticism about Justification
Goldman wants to provide a fully general account of justified belief.
His main claim is that what makes a belief justified is that it is formed by a reliable belief forming process.
Introduction
Introduction
If he is right, then we will have a good response to the skeptical argument about justification.
Goldman explains what he wants from a philosophical theory of justification:
1. A theory that explains and makes sense of our ordinary attributions of knowledge and justification.
Desiderata
2. Non-circular– Don’t provide an account of justification by
employing other epistemic terms (warrant, reasons, knowledge, good grounds, etc.)
Desiderata
3. Not merely extensionally correct.– He wants an account that agrees with all (or most)
of our judgments about individual cases.– But he also wants his account to be explanatory.– He wants to be able to say why a particular belief
is justified when others are not.
Desiderata
Goldman thinks that whether or not a belief is justified depends on whether or not the belief was formed by a good or bad process.
Belief-Forming Processes
Belief-Forming Processes
Belief-Forming Process: An operation or procedure that takes an input (e.g. perception, memorial experience, testimony, other beliefs) and outputs a belief.
Bad Belief-Forming Processes:
1. Confused reasoning2. Wishful thinking3. Reliance on emotional reactions4. Mere hunches or guesswork5. Hasty generalization
What do these have in common?– They are unreliable.
Belief-Forming Processes
Good Belief-Forming Processes :1. Good reasoning2. Perception3. Remembering4. Introspection5. Properly carried out induction or abduction
What do these have in common?• They are reliable.
Belief-Forming Processes
Processes like perception, good reasoning, and memory typically furnish us with justified beliefs.
Processes like fallacious reasoning, wishful thinking, and hasty generalization typically furnish us with unjustified beliefs.
Belief-Forming Processes
Nice Features:1. Picks out the intuitively good processes from
the bad ones.2. Makes sense of the connection between
justification and truth. 3. Allows us to make sense of the fact that
justification comes in degrees.
Belief-Forming Processes
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Goldman’s Basic Idea:If a belief is formed by reliable process it is justified, and if it is formed by unreliable process, it is unjustified.
Belief-Forming Processes
What is reliability?
• Reliability has to do with the ratio of true beliefs to false beliefs formed by using a particular process.
Reliability
Reliability
There are problems if “reliable” just means: yielded more true beliefs than false ones.
A long series of lucky guesses is reliable according to this definition, but such beliefs are not justified.
Reliability
We also need to add in how the process would perform if things had been different.
Such conditions are called counterfactual conditions.
How reliable must a belief-forming process be in order to confer justification?– Perfect reliability does not seem to be a plausible
condition.
Justification requires a high degree of reliability, but not perfect reliability.
Reliability
Reliabilism (First Formulation)If S’s believing p results from a reliable cognitive belief-forming process, then S’s belief in p is justified.
Reliabilism
Meets Goldman’s desiderata:– Reliability was defined in terms of a ratio between
true and false beliefs, hence it is reductive in the way that Goldman wants. (no epistemic terms)
– It is also explanatory. It tells us why beliefs are justified: if the that produce them reliably produce true beliefs this is a good explanation for why we should believe the thing.
Reliabilism
• Any reasoning process relies for its reliability on factual or likely input beliefs.– If you have a logically valid argument, it seems in one
sense to be perfectly reliable: given true beliefs you get only true beliefs out.
– However, it becomes immediately unreliable if you start with false beliefs.
– Ditto memory.– Ditto testimony?
A Problem
1. Belief Dependent vs. Belief Independent • Some belief forming processes take other
beliefs as inputs.– E.g. deductive reasoning, abductive reasoning,
inductive reasoning,
• Call such belief-dependent belief-forming processes.
Two Distinctions
1. Belief Dependent vs. Belief Independent • Some belief forming processes are that
include no beliefs as inputs:– E.g. introspection, perception,
• Call such belief-independent belief-forming processes.
Two Distinctions
2. Conditional vs. Unconditional Reliability
Conditional reliability: A belief-forming process is conditionally reliable if it yields a high true/false belief ratio given true input beliefs.
Unconditional reliability: A belief-forming process is unconditionally reliable if it yields a high true/false belief ratio.
Two Distinctions
• What matters for belief-dependent belief-forming is conditional reliability.
• What matters for belief-independent s is unconditional reliability.
Two Distinctions
Reliabilism (Official formulation)1. If S’s belief in p at t results from a belief-
independent process and that process is reliable, then S’s belief in p at t is justified.
2. If S’s belief in p at t results from a belief-dependent process that is conditionally reliable, and if the input beliefs on which this process operates are themselves justified, then S’s belief in p at t is justified.
3. These are the only ways for a belief to be justified.
Reliabilism
(1) If S’s belief in p at t results from a belief-independent process and that process is reliable, then S’s belief in p at t is justified.
This is just Goldman’s first attempt, applied only to belief-independent processes.
Reliabilism
(2) If S’s belief in p at t results from a belief-dependent process that is conditionally reliable, and if the input beliefs on which this process operates are themselves justified, then S’s belief in p at t is justified.
The added condition deals with the problem presented by belief-dependent processes
Reliabilism
Reliabilism
Good features of reliabilism1. Accounts for the justified beliefs of children and
smart animals.2. Accounts for our justified beliefs based on
perception, memory, and so on.3. Does a good job of discriminating between good
belief-forming methods and bad ones.4. Gives us an explanation as to why certain of our
beliefs are justified and others are not.
The anti-skeptical strategy is very similar Moore’s. One could think of it as filling in the details behind his argument.
Against Skepticism
Against Skepticism
Remember Moore’s anti-skeptical argument:1. There is a table here.2. If there is a table here, then I am not in the
Matrix.3. Therefore, I am not in the Matrix.
Against Skepticism
Moore just claimed to know (1) without any argument.
But with Goldman, we have an actual theory that supports the premise.
1. There is a table here.
Perception is a reliable belief-forming process, and I form this belief on the basis of perception. So this belief is justified.
Against Skepticism
2. If there is a table here, then I am not in the Matrix.
Stipulated by the features of the case.
Against Skepticism
3. Therefore, I am not in the Matrix.
Inferred from (1) and (2) by valid deductive inference. (1) and (2) are both justified beliefs, and deductive inference is a conditionally reliable process.
By the second clause of Goldman’s analysis 3 is also justified.
Against Skepticism
But Wait…
Couldn’t the skeptic respond as follows:– I don’t grant that you know your perception is
reliable.– In the Matrix your perceptions are radically
unreliable.– If you can’t tell the difference how can you claim
to be justified?
Goldman’s Response
Goldman’s theory does not require that you must know that your belief-forming method is reliable.
It is enough that it is.
Goldman’s Response
Of course you can come to know your perception is reliable, but that is not required to justify belief that there is a table here.
Turn your papers in!
Please turn your papers in to your TA when they arrive.
If you have Jenna, put your paper on the table at the front of class.
The New Matrix Problem• I am not in the Matrix just as I believe.• But imagine Jim, who is in the Matrix, and has
been fed experiences just like mine his whole life
I am reliable and he is not.
Objections to Reliabilism
The New Matrix Problem
• The reliabilist has to say that I am justified in my beliefs, but Jim is not.
• But how could this be? Jim’s evidence is exactly identical to mine!
Objections to Reliabilism
Bad (Reliable) Belief-Forming Processes
We can imagine cases in which intuitively bad processes are employed generating reliably true beliefs– Norman the clairvoyant. (BonJour)– Lucy and the benevolent demon. (Goldman)
Objections to Reliabilism
Other Responses to Skepticism
1. Transcendental Arguments (Kant)2. Idealism (Berkeley)3. Coherentism (BonJour)4. Contextualism (Cohen, DeRose, Lewis)5. Truth-tracking views (Nozick)6. Hinge propositions (Wittgenstein, Wright)