PHIL1003 Lecture 1: Lecture 1B - Epistemology
Epistemology:
Theory of knowledge.
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We claim to know things.
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What is knowledge, do we have any?
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Epistemological questions:
What's the nature/definition of knowledge?
Can we say, in a clear way "does someone know this"
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What makes a belief rational?
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What kinds of facts do we know?
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What are the sources of knowledge?
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Which sources of knowledge are basic?
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Types of Knowledge
Tripartite model of knowledge
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Acquaintance Knowledge:
"Anne knows Bob"
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This person has knowledge of this other person/this place/object.
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You have knowledge of something by coming into direct contact with
the person.
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Procedural Knowledge (knowledge-how):
"Dan knows how to juggle"
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Knowing how to do something/skils
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Propositional Knowledge (knowledge-that):
"Fred knows that dinosaurs are extinct"
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Knowledge of facts.
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Knowing certain things are the case.
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What are Propositions:
Key notion in epistemology.
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Not the same as sentences/statements.
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Different sentences express the same proposition.
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Propositions are:
The contents of beliefs and other mental states.
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The fundamental bearers of truth and falsity.
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They are posited to play these theoretical roles.
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The Analysis of Knowledge
Key question in epistemology:
What conditions are necessary for a person to know a given
proposition?
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Are those conditions also sufficient?
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But… what is knowledge?
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Necessary Conditions for Knowing:
If we can identify a necessary condition for knowledge, it will look like this:
S knows that P only if ___
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"A given shape is an equilateral triangle only if it has three sides.
Its necessary, but not sufficient.
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Question 1: Is Belief Necessary?
To know something is true, you have to believe that something is true.
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Digression: The Concept of Belief
'Belief' is sometimes used in such a way that it and knowledge are mutually
exclusive:
If you believe, then you don’t know
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If you know, then you don’t need belief.
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But sometimes it gets used in another way:
'To believe that P' just means 'to sincerely think that P is true'.
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Which is how we will be using it ^
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'sincerely thinks it’s the case'
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Belief is a Necessary Condition for Knowledge
You cant know Paris is the capital of France if you don’t even believe it is.
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Upshot: To know that P, you must believe that P.
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S knows that P only if S believes that P
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The Belief Theory
The 'Belief Theory' says that belief is both necessary and sufficient for
knowledge:
S knows that P if and only if S believes that P.
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Problems:
Beliefs can be untrue.
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Some beliefs don’t have proper justification.
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Truth is a Necessary Condition
To know a proposition, it's not enough just to believe the proposition.
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The proposition also has to be true.
You can't know what ain't so.
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Truth is also a necessary condition for knowledge.
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An Argument Against the Belief Theory
The observation that truth is a necessary condition for knowledge gives us an
argument against the belief theory of knowledge:
P1. If the believe theory is true, then Smith knows that Jones did it.
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P2. Smith does not know that Jones did it.
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C. The belief theory is false.
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Belief is necessary and truth is necessary.
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Necessary and Sufficient?
Are belief and truth jointly sufficient for knowledge?
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The True Belief Theory
Says truth and belief are individually necessary and jointly sufficient for
knowledge:
S knows that P if and only if (a) S believes that P and (b) P is true.
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Justification is a Necessary Condition
To know a proposition, it's not enough just to have a true belief.
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Lucky or accidental true beliefs aren't knowledge.
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You also have to have (good) reasons or evidence for believing it.
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One way of putting this: your belief must be justified.
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The Justified True Belief Theory
JTB theory, or analysis of knowledge:
S knows that P if and only if:
S believes that P
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P is true
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S is justified in believing that P.
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On this view, justification, truth, and belief are individually necessary and
jointly sufficient for knowledge.
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Epistemic vs. Pragmatic Justification
Note: the relevant kind of justification is epistemic justification - roughly
synonymous with 'evidence'.
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Pragmatic or practical justification is different.
E.g. suppose you have a serious illness with only a 1 in 10 chance of
recovery.
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But you know that people with this illness who believe they will recover
have a 3 in 10 chance.
You are pragmatically, but not epistemically, justified in believing
you will recover.
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You have good practical reasons for adopting this belief - but not
objectively compelling evidence.
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Is JBT Enough?
JTB analysis has a long history in philosophy.
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“S knows that h is true” means: (i) S accepts h; (ii) S has adequate evidence for
h; and (iii) h is true” (Chisholm 1958, p. 17)
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Lecture 1B
Tuesday, 31 July 2018
10:57 am
Document Summary
Can we say, in a clear way "does someone know this" This person has knowledge of this other person/this place/object. You have knowledge of something by coming into direct contact with the person. The contents of beliefs and other mental states. They are posited to play these theoretical roles. If we can identify a necessary condition for knowledge, it will look like this: "a given shape is an equilateral triangle only if it has three sides. To know something is true, you have to believe that something is true. "belief" is sometimes used in such a way that it and knowledge are mutually exclusive: If you know, then you don"t need belief. "to believe that p" just means "to sincerely think that p is true". Which is how we will be using it ^ You cant know paris is the capital of france if you don"t even believe it is. Upshot: to know that p, you must believe that p.
