7 ideas
| 12129 | 'Truth' may only apply within a theory [Kuhn] |
| Full Idea: 'Truth' may, like 'proof', be a term with only intra-theoretic applications. | |
| From: Thomas S. Kuhn (Reflections on my Critics [1970], §5) | |
| A reaction: I think we can blame Tarski (via Quine, Kuhn's teacher) for this one. I take it to be an utter failure to grasp the meaning of the word 'truth' (and sneakily substituting 'satisfaction' for it). For a start, we have to compare theories on some basis. |
| 9987 | An aggregate in which order does not matter I call a 'set' [Bolzano] |
| Full Idea: An aggregate whose basic conception renders the arrangement of its members a matter of indifference, and whose permutation therefore produces no essential difference, I call a 'set'. | |
| From: Bernard Bolzano (Paradoxes of the Infinite [1846], §4), quoted by William W. Tait - Frege versus Cantor and Dedekind IX | |
| A reaction: The idea of 'sets' was emerging before Cantor formalised it, and clarified it by thinking about infinite sets. Nowadays we also have 'ordered' sets, which rather contradicts Bolzano, and we also expect the cardinality to be determinate. |
| 10856 | A truly infinite quantity does not need to be a variable [Bolzano] |
| Full Idea: A truly infinite quantity (for example, the length of a straight line, unbounded in either direction) does not by any means need to be a variable. | |
| From: Bernard Bolzano (Paradoxes of the Infinite [1846]), quoted by Brian Clegg - Infinity: Quest to Think the Unthinkable §10 | |
| A reaction: This is an important idea, followed up by Cantor, which relegated to the sidelines the view of infinity as simply something that could increase without limit. Personally I like the old view, but there is something mathematically stable about infinity. |
| 2614 | Modern phenomenalism holds that objects are logical constructions out of sense-data [Ayer] |
| Full Idea: Nowadays phenomenalism is held to be a theory of perception which says that physical objects are logical constructions out of sense-data. | |
| From: A.J. Ayer (Phenomenalism [1947], §1) |
| 2615 | The concept of sense-data allows us to discuss appearances without worrying about reality [Ayer] |
| Full Idea: The introduction of the term 'sense-datum' is a means of referring to appearances without prejudging the question of what it is, if anything, that they are appearances of. | |
| From: A.J. Ayer (Phenomenalism [1947], §1) |
| 6809 | Kuhn came to accept that all scientists agree on a particular set of values [Kuhn, by Bird] |
| Full Idea: Kuhn later came to accept that there are five values to which scientists in all paradigms adhere: accuracy; consistency with accepted theories; broad scope; simplicity; and fruitfulness. | |
| From: report of Thomas S. Kuhn (Reflections on my Critics [1970]) by Alexander Bird - Philosophy of Science Ch.8 | |
| A reaction: To shake off the relativism for which Kuhn is notorious, we should begin by asking the question WHY scientists favoured these particular values, rather than (say) bizarreness, consistency with Lewis Carroll, or alliteration. (They are epistemic virtues). |
| 12128 | In theory change, words shift their natural reference, so the theories are incommensurable [Kuhn] |
| Full Idea: In transitions between theories words change their meanings or applicability. Though most of the signs are used before and after a revolution - force, mass, cell - the ways they attach to nature has changed. Successive theories are thus incommensurable. | |
| From: Thomas S. Kuhn (Reflections on my Critics [1970], §6) | |
| A reaction: A very nice statement of the view, from the horse's mouth. A great deal of recent philosophy has been implicitly concerned with meeting Kuhn's challenge, by providing an account of reference that doesn't have such problems. |