8 ideas
8207 | The quest for simplicity drove scientists to posit new entities, such as molecules in gases [Quine] |
Full Idea: It is the quest for system and simplicity that has kept driving the scientist to posit further entities as values of his variables. By positing molecules, Boyles' law of gases could be assimilated into a general theory of bodies in motion. | |
From: Willard Quine (On Multiplying Entities [1974], p.262) | |
A reaction: Interesting that a desire for simplicity might lead to multiplications of entities. In fact, I presume molecules had been proposed elsewhere in science, and were adopted in gas-theory because they were thought to exist, not because simplicity is nice. |
8208 | In arithmetic, ratios, negatives, irrationals and imaginaries were created in order to generalise [Quine] |
Full Idea: In classical arithmetic, ratios were posited to make division generally applicable, negative numbers to make subtraction generally applicable, and irrationals and finally imaginaries to make exponentiation generally applicable. | |
From: Willard Quine (On Multiplying Entities [1974], p.263) | |
A reaction: This is part of Quine's proposal (c.f. Idea 8207) that entities have to be multiplied in order to produce simplicity. He is speculating. Maybe they are proposed because they are just obvious, and the generality is a nice side-effect. |
8205 | Explaining events just by bodies can't explain two events identical in space-time [Quine] |
Full Idea: An account of events just in terms of physical bodies does not distinguish between events that happen to take up just the same portion of space-time. A man's whistling and walking would be identified with the same temporal segment of the man. | |
From: Willard Quine (On Multiplying Entities [1974], p.260) | |
A reaction: We wouldn't want to make his 'walking' and his 'strolling' two events. Whistling and walking are different because different objects are involved (lips and legs). Hence a man is not (ontologically) a single object. |
8206 | Necessity could be just generalisation over classes, or (maybe) quantifying over possibilia [Quine] |
Full Idea: The need to add a note of necessity to 'all black crows are black' could be met by a generalisation over classes (what belongs to sets x and y belongs to y), or maybe be quantifying over possible particulars. | |
From: Willard Quine (On Multiplying Entities [1974], p.262) | |
A reaction: He dislikes the second strategy because 'unactualized particulars are an obscure and troublesome lot'. The second is the strategy of Lewis. I think necessity starts to creep back in as soon as you ask WHY a generalisation holds true. |
20795 | Some things are their own criterion, such as straightness, a set of scales, or light [Sext.Empiricus] |
Full Idea: Dogmatists say something can be its own criterion. The straight is the standard of itself, and a set of scales establishes the equality of other things and of itself, and light seems to reveal not just other things but also itself. | |
From: Sextus Empiricus (Against the Mathematicians [c.180], 442) | |
A reaction: Each of these may be a bit dubious, but deserves careful discussion. |
20794 | How can sceptics show there is no criterion? Weak without, contradiction with [Sext.Empiricus] |
Full Idea: The dogmatists ask how the sceptic can show there is no criterion. If without a criterion, he is untrustworthy; with a criterion he is turned upside down. He says there is no criterion, but accepts a criterion to establish this. | |
From: Sextus Empiricus (Against the Mathematicians [c.180], 440) | |
A reaction: This is also the classic difficulty for foundationalist views of knowledge. Is the foundation justified, or not? |
3158 | Theories of intentionality presuppose rationality, so can't explain it [Dennett] |
Full Idea: Intentional theory is vacuous as psychology because it presupposes and does not explain rationality or intelligence. | |
From: Daniel C. Dennett (Brainstorms:Essays on Mind and Psychology [1978], p.15?) | |
A reaction: Virtually every philosophical theory seems to founder because it presupposes something like the thing it is meant to explain. I agree that 'intentionality' is a slightly airy concept that would probably reduce to something better. |
3159 | Beliefs and desires aren't real; they are prediction techniques [Dennett] |
Full Idea: Intentional systems don't really have beliefs and desires, but one can explain and predict their behaviour by ascribing beliefs and desires to them. This strategy is pragmatic, not right or wrong. | |
From: Daniel C. Dennett (Brainstorms:Essays on Mind and Psychology [1978], p.7?) | |
A reaction: If the ascription of beliefs and desires explains behaviour, then that is good grounds for thinking they might be real features of the brain, and even if that is not so, they are real enough as abstractions from brain events, like the 'economic climate'. |