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Contents EMPIRICISM PHIL3072, ANU, 2015 Jason Grossman http://empiricism.xeny.net (extremely brie y and out of order) Kant and rationalism (fairly brie y) recap (medium speed) Locke's radical empiricism (relaxedly) rationalism — case studies lecture 3: 4 August John Locke's Radical Empiricism Ideas idea is Locke's terminology for sensations = experiences = phenomena includes beliefs, knowledge, reasoning, and self-awareness Tabula rasa Desired conclusion: “Let us then suppose the mind to be, as we say, white paper, void of all characters, without any ideas” (Book 2, chapter 1). — All citations in this lecture are to John Locke's “Essay Concerning Human Understanding” unless otherwise speci ed. I'm using the (confusingly, Locke calls self-awareness “intution”, but it's still an idea) so it refers to (arguably) anything mental. All ideas are perceived 12th edition of “The Works of John Locke in Nine Volumes” London: Rivington, 1824, but you can cite one of the versions on the web if you prefer. Problem: how can we ever get knowledge if we start as a tabula rasa? so none are a priori. Even innate ideas — if there are any — are perceived. How ideas represent the external world Clockwork! “the understanding, in its view of them, considers [black and white, heat and cold etc.] as distinct positive ideas, without taking notice of the causes that produce them: which is an inquiry not belonging to the idea, as it is in the understanding, but to the nature of the things existing without us. “primary qualities of body . . . we may observe to produce simple ideas in us, viz. solidity, extension, gure, motion or rest, and number.” These are two very different things, and carefully to be distinguished; it being one thing to perceive and know the idea of white or black, and quite another to examine what kind of particles they must be, and how ranged in the super cies, to make any object appear white or black.” — Book 2, chapter 8 “colours, sounds, tastes, &c” are secondary qualities; causal powers are “a third sort”, and certainly not primary. “The next thing to be considered is, how bodies produce ideas in us; and that is manifestly by impulse, the only way which we can conceive bodies to operate in.” — Book 2, chapter 8 How ideas represent the external world: resemblance “the ideas of [only] primary qualities of bodies are resemblances of them, and their patterns do really exist in the bodies themselves” Knowledge “Knowledge is the perception of the agreement or disagreement of two ideas.” — Book 2, chapter 8 Plausible given how broad “idea” is: if ideas include everything mental, then perhaps all knowledge is comparison of ideas. Watch this space for Berkeley's commentary on this claim. “Since the mind, in all its thoughts and reasonings, hath no other immediate object but its own ideas, which it alone does or can contemplate, it is evident that our knowledge is only conversant about them.” Locke sort of means this seriously. By “agreement or disagreement”, Locke means something rather complicated. Contradiction with the claim that we can know the primary qualities of bodies? What about knowledge of simple ideas (which Locke says we have)? “This agreement or disagreement may be any of four sorts.” . . . Types of knowledge I. Of identity, or diversity in ideas II. “Of abstract relations between ideas” “By this the mind clearly and infallibly perceives each idea to agree with itself, and to be what it is; and all distinct ideas to disagree, i.e. the one not to be the other” “the perception of the relation between any two ideas, of what kind soever, whether substances, modes, or any other. For, since all distinct ideas must eternally be known not to be the same, and so be universally and constantly denied one of another, there could be no room for any positive knowledge at all, if we could not perceive any relation between our ideas, and nd out the agreement or disagreement they have one with another, in several ways the mind takes of comparing them.” III. “Of their necessary co-existence in substances” “co-existence or non-co-existence in the same subject; and this belongs particularly to substances. IV. “Of real existence agreeing to any idea” IV. “Of real existence agreeing to any idea . . . without [outside] the mind” Thus when we pronounce concerning gold, that it is xed, our knowledge of this truth amounts to no more but this, that xedness, or a power to remain in the re unconsumed, is an idea that always accompanies and is joined with that particular sort of yellowness, weight, fusibility, malleableness, and solubility in aqua regia, which make our complex idea signi ed by the word gold.” This claim was much more in uential when Hume repeated it 50 years later. The only example given is“God is”. The idea of God is in some sense innate, but de nitely not a priori. God is often an exception in Early Modern epistemologies (contrast with mediaeval and contemporary epistemologies). It's up to us poor historians to guess how seriously to take these exceptions. :-( . — Book 4, chapter 1 How the mind acquires ideas from the external world Arguments that sensations are caused by material objects “we can have knowledge no further than we have ideas” Three questionable arguments: — Book 4, chapter 3 2. Our sense organs do not produce sensations themselves, or else “the eyes of a man in the dark would produce colours”. “we have the knowledge of our own existence by intuition; of the existence of God by demonstration; and of other things by sensation” — Book 4, chapter 9 5 arguments that sensations are caused by material objects . . . 3. “I can at pleasure recall to my mind the ideas of light, or the sun, which former sensations had lodged in my memory . . . But, if I turn my eyes at noon towards the sun, I cannot avoid the ideas which the light or sun then produces in me.” 4. “because pleasure or pain, which accompanies actual sensation, accompanies not the returning of those ideas without the external objects” And two much better arguments . . . Arguments that sensations are caused by material objects 1. “I can no more doubt, whilst I write this, that I see white and black, and that something really exists that causes that sensation in me, than that I write or move my hand; which is a certainty as great as human nature is capable of, concerning the existence of anything, but a man's self alone, and of God. This notice by our senses, though not so certain as demonstration, yet may be called knowledge, and proves the existence of things without us.” “I think nobody can, in earnest, be so sceptical as to be uncertain of the existence of those things which he sees and feels. At least, he that can doubt so far, (whatever he may have with his own thoughts,) will never have any controversy with me; since he can never be sure I say anything contrary to his own opinion.” clever argument, to be varied slightly by Hume Arguments that sensations are caused by material objects 5. “because our senses assist one another's testimony of the existence of outward things, and enable us to predict” This idea is developed in great detail in 20th-century philosophy of science; but there are counter-arguments. (See Arthur Fine, much later in the course.) — Book 4, chapter 11 .