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KNOWLEDGE What is it? How does it differ from belief? What is the relationship between knowledge and truth? These are the concerns of epistemology How do we acquire it? What is its scope – how far does it extend? Is it necessary to be able to convince someone else that what I claim as an item of knowledge is more than mere belief? Knowledge Definitions (1) [1] How about knowledge as something more certain than mere belief? When we are in an infallible state of mind? But, there are counter-instances where despite being convinced we are later shown to be wrong by newly emerging facts. Should we therefore ground knowledge in objective reality not subjective belief? You can always count on a Greek for a point of view in philosophy And usually this is PLATO Knowledge Definitions (2) [2] Have knowledge and belief different objects? Plato at one point held something like this. Later he seems to say that to know something is to believe it and provide an adequate account – an analysis or definition of essential features. So, is knowledge equal to belief plus understanding? Mind you, Plato isn’t the only top Greek philosopher There is always Aristotle if you are looking for a second opinion Knowledge Definitions (3) Whereas Plato seemed not to be interested in justification or certainty, Aristotle perhaps was. Aristotle (uncritically) recognised the given of sense-data and the notion of causes as certain. Knowledge of a particular thing presupposes a quest for an explanation or ‘ultimate’ cause. Knowledge Definitions (4) A.J. Ayer (1910-89) holds along with many modern philosophers that knowledge and belief have the same objects. His definition: Knowledge is justified true belief. TRUTH theories about truth Several views are current on the issue of ‘Pilate’s question’ PRAGMATIC THEORY COHERENCE THEORY CORRESPONDANCE THEORY REDUNDANCY THEORY PRAGMATISM US philosophers Charles Pierce (1839-1914) & William James (1842-1910). “True ideas are those that we can assimilate, validate, corroborate and verify. False ideas are those we cannot.” - James “it is useful because it is true….it is true because it is useful” - James American pragmatists were all the rage at the turn of the century This is Charles Sanders Pierce You should be aware too of the importance of John Dewey and of William James Mind you, not everyone was a fan of pragmatism For example our own, our very own, Bertrand Russell. PRAGMATISM objections Many of these made by Bertrand Russell: The notion of ‘works for me/us’ is ambiguous. In everyday discourse we distinguish between ‘useful’ & ‘truth’. James is redefining these terms in his identification of one with the other. ‘Working for us’ is problematic because it is almost impossible to determine the consequences of holding a particular belief. Back in the 19th cc Idealists were all the rage One of the top men was the unique figure of George Hegel whose writings are not always transparent! COHERENCE by 18th&19th cc idealists such as G.W.F.Hegel & F.H.Bradley. A statement is true if it ‘coheres’ or ‘fits in’ with other statements thereby forming a complete system. Advocated COHERENCE Critical remarks There is more than one possible coherent system. Coherence requires the notion of logical consistency which in turn requires the notion of logically prior truth and falsity (as more than defined by coherence theory). Internally coherent systems cannot say anything about the relation of the system to the world. COHERENCE MAY BE A TEST OF TRUTH BUT IT CANNOT TELL US WHAT TRUTH MEANS. CORRESPONDANCE 1 Russell argued that any theory of truth must satisfy these three criteria: [1] It must admit of its opposite - falsehood. [2] Truth and falsity must be properties of beliefs and statements. [3] These properties depend on the relation of these statements to something outside those beliefs. CORRESPONDANCE 2 If a belief is true it must correspond to a fact of some kind which ‘exists’ in the world. One objection is that it is the meaning of statements or beliefs which count, and this is what a proposition (p) is. Propositions rather than beliefs carry truth or falsity. I should say “p is true and I believe it” rather than “I believe p”. CORRESPONDANCE 3 This view entails the need to be very specific with propositions to avoid the charge that p can sometimes be true and sometimes false. The second difficulty is in the question, ‘Can propositions be distinguished from the facts that they are supposed to correspond to, and if so, how?’ ie. How do we get outside of our language? cf. Wittgenstein. Wittgenstein is viewed by many as the greatest 20th cc philosopher Encouraged by Russell to get stuck into philosophy at Cambridge, he was later to eclipse the old man, who reacted, it is rumoured, with a touch of jealousy! CORRESPONDANCE 4 An objection to Russell’s account (Problems of Philosophy XII) is that propositions have a funny sort of existence between ourselves and the supposed ‘outside world’. Might not a true proposition be a fact itself? Why the distinction, which is needed if the correspondance is possible? What is meant by ‘objective existence’ here? CORRESPONDANCE 5 According to Russell there is a correspondance between a belief and a fact when (a) there is a complex unity of object terms and an object relation, and (b) when the order of these terms and relations is ‘in the same order as they have in the belief’. The judgement having a ‘sense’ or ‘direction’. How do we get outside our language? REDUNDANCY 1 Originally proposed by F.P. Ramsay and later modified by P.F. Strawson. Utilises what J.L.Austin called ‘performatives’. Hence in Strawson it is the Performatory theory. We make the notion of truth redundant by saying that when we say that x is true, we do no more than to say that we agree to accept x. Will this do? How do we know what to accept?