What is knowledge?

“The objective of the analysis of knowledge is to state conditions that are individually necessary and jointly sufficient for propositional knowledge.” – Stanford

Encyclopaedia of Philosophy

Kinds of knowledge

• (Some) kinds of knowledge:– Procedural knowledge or knowing how e.g. to ride a

bicycle– Personal knowledge or direct acquaintance e.g

knowing Lewisham, or Beethoven’s symphonies– Knowing who e.g. identifying faces– Knowing that: of interest to philosophers

• Any knowledge that can be phrased ‘I know that X’, where X is an assertion or statement is called propositional knowledge.

Test: what kind?

1. I know what Brad Pitt looks like.2. I know how to get to Nunhead.3. We know who you are.4. We know where you live.5. I can make lemon drizzle cake.6. I recall Mount Everest’s height.7. I know Berkeley is an idealist.8. I know Berkeley.9. I recognise that girl.

1. Knowing who.2. Acquaintance/Procedural.3. Knowing who.4. Propositional (arguably)5. Procedural.6. Propositional.7. Propositional.8. Knowing who.9. Knowing who.

Knowing and Opining

• The difference between knowledge and belief or opinion:– Knowledge: certainty, indubitability, being

proven vs Opinion: degrees of plausibility, assent, being unproven.

– Knowledge: impossible to know something that is false vs Opinion: possible to believe something that is mistaken.

– Knowledge which is certain vs ‘knowledge-claims’ which are not yet proven.

Plato’s tripartite definition• Now: conceptual analysis – the Rationalist

approach– What are the sufficient conditions for knowledge?

• Read the extract from the ‘Meno’– What three components is knowledge composed

of?– What is the difference between knowledge and

true belief?– And how might we refer to this in modern

parlance?

6. Extract from Plato’s ‘Meno’: knowledge as tripartiteSOCRATES: I will explain. If a man knew the way to Larissa, or anywhere else, and went to the place and led others thither, would he not be a right and good guide?MENO: Certainly.SOCRATES: And a person who had a right opinion about the way, but had never been and did not know, might be a good guide also, might he not? While he has true opinion about that which the other knows, he will be just as good a guide if he thinks the truth, as he who knows the truth?MENO: Exactly.SOCRATES: Then true opinion is as good a guide to correct action as knowledge…right opinion is not less useful than knowledge?MENO: The difference, Socrates, is only that he who has knowledge will always be right; but he who has right opinion will sometimes be right, and sometimes not.SOCRATES: Exactly! [Here is] an illustration of the nature of true opinions: while they abide with us they are beautiful and fruitful, but do not remain long, and therefore they are not of much value until they are fastened by the tie of the cause. ..But when they are bound, they have the nature of knowledge, they are abiding. And this is why knowledge is more honourable and excellent than true opinion, because fastened by a chain.MENO: What you are saying, Socrates, seems to be very like the truth: knowledge differs from true opinion.

What Plato is saying: ‘Luck is Yuck!’• Knowledge = True Belief + ‘a chain’ (of evidence)• This is because

– both knowledge (that is certain) and a belief (that happens to be right) about the best way to Lewisham may get you good directions to Lewisham

– But the belief that happens to be right is only right by accident (say: a lucky guess about the best way)

– Whereas the knowledge that is certain is correctly justified so cannot be mistaken (say: you have walked the route many times so simply can’t be wrong about it)

– So if your true belief has justification it must be correct

JTB in Standard Form

• Also called the ‘Tripartite Account’

• In Standard Form:– ‘S knows that P’ iff

1. P is true 2. S believes that P3. S is justified in

believing that P

Note:

1. S is any subject/ person making a knowledge-claim.

2. P is any proposition (a statement of the form ‘X is Y’ e.g. ‘Derek is fat’.

Explanation: what is a belief?• Often called the ‘psychological’

or ‘internal’ criterion for knowledge

• The mental attitude we have towards a proposition when we hold it to be true, or to be the case

• Actually or potentially holding a proposition before your mind and assenting to it

• Can be held without active reflection – most of our beliefs are unconscious

• [Can be a matter of degree, or scalar]

Explanation: what is Truth?• Truth is a property only of propositions…• It is not a property of the world…which just is• Often called the ‘external’ criterion for knowledge• Some theories of truth…

– Correspondence – ‘Truth corresponds to the world’– Coherence – ‘Truth fits with other truths’– Pragmatism – ‘Truth is what works’– Deflationary/Minimalist theories – ‘Truth adds nothing’ –

except approval.

Explanation: what is justification?• Often called the ‘justification

condition’.• Connects truth and belief.• There are various theories of

justification e.g. coherentism, reliabilism, foundationalism.

• All seek to explain how mental content can be connected to the world.

• All can be seen as clarifying the justification condition of the tripartite account.

JTB in Standard Form, revised• ‘S knows that P’ iff

1. P is true 2. S believes that P3. [S is justified in believing that P] can be

revised to:a) [coherentism] P is justified iff it fits with other

beliefs that are held.b) [reliabilism] P is justified iff the belief that P

is produced by a good method.c) [foundationalism] P is justified iff P rests on

a basic and indubitable belief.

Coherentism• P is justified iff it fits with other beliefs that are held.• So the process of justification has no ultimate ground.• Rather the justification of a belief consists in the way it

fits in or makes sense with other beliefs that one holds. • Key image: not foundations, but a web of beliefs.

– Justification is fit, and the better the fit, the better the justification.– Belief-systems are internally consistent, and the beliefs mutually

supporting.• a good way of explaining how belief-systems change:

one belief (Santa Claus existing) simply stops fitting with another one…

Reliabilism

• P is justified iff the belief that P is produced by a good method.

• the infinite regress of justification can be halted using beliefs that are the results of a sound method or a process that has worked in the past– if in the past the method has led to a successful prediction,

diagnosis, description, identification or explanation…– then it can be trusted again.

• Good methods of justification would therefore include: the senses, memory, testimony of others known to be truthful, inductive and deductive reasoning and so on.

• This approach rules out luck, but is a ‘black box’ theory: doesn't require you to understand how a view is arrived at.

Foundationalism

• P is justified iff P rests on a basic and indubitable belief.• There are basic beliefs that are self-evident and don’t

need justification.• There are two versions of this view:

– The best basic beliefs are rationally discovered and self-evident statements: truths of reason underlie and ultimately justify all our knowledge-claims.

– OR The best basic beliefs arise from simple observation: sensory truths underlie and ultimately justify all our knowledge-claims.

Foundationalism recap

• P is justified iff P rests on a basic and indubitable belief.• There are basic beliefs that are self-evident, non-

inferential and don’t themselves need justification.• There are two versions of this view:

– RATIONALISM: The best basic beliefs are rationally discovered and self-evident statements: truths of reason underlie and ultimately justify all our knowledge-claims.

– EMPIRICISM: The best basic beliefs arise from simple observation: sensory truths underlie and ultimately justify all our knowledge-claims.

Incomplete Examiner’s Notes for 9-mark question: Q4 - Outline and explain the tripartite view of knowledge

(‘Justified True Belief’).• Only about __________ knowledge – ‘s knows that p’.• Gives ________ conditions that are each _________ and taken together

sufficient for s to know p.• Condition 1 – s knows that p only if s _____________. It is impossible for a

person to know a proposition without believing that proposition. This is sometimes called the ____________ or ‘internal’ criterion.

• Condition 2 – s knows that p only if p is true. It is impossible for a person to know a proposition that is _______. When a false _______ is held it is merely a ______. Beliefs can be ______ or false. Knowledge can only be true (distinction between ‘knowledge’ and ‘knowledge-_________’). This is sometimes called the ____________criterion.

• Condition 3 – s knows that p only if s is justified in believing p. This condition is required because it is possible to have a _____________that would not, at least intuitively, count as knowledge, e.g. lucky guesses. For a person to __________ a proposition they must have a reason/grounds for holding that belief. There are various theories of justification.