9 ideas
19463 | Induction assumes some uniformity in nature, or that in some respects the future is like the past [Ayer] |
Full Idea: In all inductive reasoning we make the assumption that there is a measure of uniformity in nature; or, roughly speaking, that the future will, in the appropriate respects, resemble the past. | |
From: A.J. Ayer (The Problem of Knowledge [1956], 2.viii) | |
A reaction: I would say that nature is 'stable'. Nature changes, so a global assumption of total uniformity is daft. Do we need some global uniformity assumptions, if the induction involved is local? I would say yes. Are all inductions conditional on this? |
19459 | To say 'I am not thinking' must be false, but it might have been true, so it isn't self-contradictory [Ayer] |
Full Idea: To say 'I am not thinking' is self-stultifying since if it is said intelligently it must be false: but it is not self-contradictory. The proof that it is not self-contradictory is that it might have been false. | |
From: A.J. Ayer (The Problem of Knowledge [1956], 2.iii) | |
A reaction: If it doesn't imply a contradiction, then it is not a necessary truth, which is what it is normally taken to be. Is 'This is a sentence' necessarily true? It might not have been one, if the rules of English syntax changed recently. |
19460 | 'I know I exist' has no counterevidence, so it may be meaningless [Ayer] |
Full Idea: If there is no experience at all of finding out that one is not conscious, or that one does not exist, ..it is tempting to say that sentences like 'I exist', 'I am conscious', 'I know that I exist' do not express genuine propositions. | |
From: A.J. Ayer (The Problem of Knowledge [1956], 2.iii) | |
A reaction: This is, of course, an application of the somewhat discredited verification principle, but the fact that strictly speaking the principle has been sort of refuted does not mean that we should not take it seriously, and be influenced by it. |
19461 | Knowing I exist reveals nothing at all about my nature [Ayer] |
Full Idea: To know that one exists is not to know anything about oneself any more than knowing that 'this' exists is knowing anything about 'this'. | |
From: A.J. Ayer (The Problem of Knowledge [1956], 2.iii) | |
A reaction: Descartes proceeds to define himself as a 'thinking thing', inferring that thinking is his essence. Ayer casts nice doubt on that. |
7458 | The reliability of witnesses depends on whether they benefit from their observations [Laplace, by Hacking] |
Full Idea: The credibility of a witness is in part a function of the story being reported. When the story claims to have infinite value, the temptation to lie for personal benefit is asymptotically infinite. | |
From: report of Pierre Simon de Laplace (Philosophical Essay on Probability [1820], Ch.XI) by Ian Hacking - The Emergence of Probability Ch.8 | |
A reaction: Laplace seems to especially have reports of miracles in mind. This observation certainly dashes any dreams one might have of producing a statistical measure of the reliability of testimony. |
19464 | We only discard a hypothesis after one failure if it appears likely to keep on failing [Ayer] |
Full Idea: Why should a hypothesis which has failed the test be discarded unless this shows it to be unreliable; that is, having failed once it is likely to fail again? There is no contradiction in a hypothesis that was falsified being more likely to pass in future. | |
From: A.J. Ayer (The Problem of Knowledge [1956], 2.viii) | |
A reaction: People may become more likely to pass a test after they have failed at the first attempt. Birds which fail to fly at the first attempt usually achieve total mastery of it. There are different types of hypothesis here. |
19462 | Induction passes from particular facts to other particulars, or to general laws, non-deductively [Ayer] |
Full Idea: Inductive reasoning covers all cases in which we pass from a particular statement of fact, or set of them, to a factual conclusion which they do not formally entail. The inference may be to a general law, or by analogy to another particular instance. | |
From: A.J. Ayer (The Problem of Knowledge [1956], 2.viii) | |
A reaction: My preferred definition is 'learning from experience' - which I take to be the most rational behaviour you could possibly imagine. I don't think a definition should be couched in terms of 'objects' or 'particulars'. |
3441 | If a supreme intellect knew all atoms and movements, it could know all of the past and the future [Laplace] |
Full Idea: An intelligence knowing at an instant the whole universe could know the movement of the largest bodies and atoms in one formula, provided his intellect were powerful enough to subject all data to analysis. Past and future would be present to his eyes. | |
From: Pierre Simon de Laplace (Philosophical Essay on Probability [1820]), quoted by Mark Thornton - Do we have free will? p.70 |
4377 | Intellectualism is an excessive emphasis on reasoning in moral philosophy [Burnyeat] |
Full Idea: Intellectualism, a one-sided preoccupation with reason and reasoning, is a perennial failing in moral philosophy. | |
From: Myles F. Burnyeat (Aristotle on Learning to be Good [1980], p.70) | |
A reaction: But Kant's reply would be that while there is much more to moral behaviour, the only part which matters in morality is the reasoning part. And Socrates' view (ignorance is evil) is not obviously wrong. |