15 ideas
5831 | The new view is that "water" is a name, and has no definition [Schwartz,SP] |
Full Idea: Perhaps the modern view is best expressed as saying that "water" has no definition at all, at least in the traditional sense, and is a proper name of a specific substance. | |
From: Stephen P. Schwartz (Intro to Naming,Necessity and Natural Kinds [1977], §III) | |
A reaction: This assumes that proper names have no definitions, though I am not clear how we can grasp the name 'Aristotle' without some association of properties (human, for example) to go with it. We need a definition of 'definition'. |
10482 | The logic of ZF is classical first-order predicate logic with identity [Boolos] |
Full Idea: The logic of ZF Set Theory is classical first-order predicate logic with identity. | |
From: George Boolos (Must We Believe in Set Theory? [1997], p.121) | |
A reaction: This logic seems to be unable to deal with very large cardinals, precisely those that are implied by set theory, so there is some sort of major problem hovering here. Boolos is fairly neutral. |
10492 | A few axioms of set theory 'force themselves on us', but most of them don't [Boolos] |
Full Idea: Maybe the axioms of extensionality and the pair set axiom 'force themselves on us' (Gödel's phrase), but I am not convinced about the axioms of infinity, union, power or replacement. | |
From: George Boolos (Must We Believe in Set Theory? [1997], p.130) | |
A reaction: Boolos is perfectly happy with basic set theory, but rather dubious when very large cardinals come into the picture. |
10485 | Naïve sets are inconsistent: there is no set for things that do not belong to themselves [Boolos] |
Full Idea: The naïve view of set theory (that any zero or more things form a set) is natural, but inconsistent: the things that do not belong to themselves are some things that do not form a set. | |
From: George Boolos (Must We Believe in Set Theory? [1997], p.127) | |
A reaction: As clear a summary of Russell's Paradox as you could ever hope for. |
10484 | The iterative conception says sets are formed at stages; some are 'earlier', and must be formed first [Boolos] |
Full Idea: According to the iterative conception, every set is formed at some stage. There is a relation among stages, 'earlier than', which is transitive. A set is formed at a stage if and only if its members are all formed before that stage. | |
From: George Boolos (Must We Believe in Set Theory? [1997], p.126) | |
A reaction: He gives examples of the early stages, and says the conception is supposed to 'justify' Zermelo set theory. It is also supposed to make the axioms 'natural', rather than just being selected for convenience. And it is consistent. |
5829 | We refer to Thales successfully by name, even if all descriptions of him are false [Schwartz,SP] |
Full Idea: We can refer to Thales by using the name "Thales" even though perhaps the only description we can supply is false of him. | |
From: Stephen P. Schwartz (Intro to Naming,Necessity and Natural Kinds [1977], §III) | |
A reaction: It is not clear what we would be referring to if all of our descriptions (even 'Greek philosopher') were false. If an archaeologist finds just a scrap of stone with a name written on it, that is hardly a sufficient basis for successful reference. |
5830 | The traditional theory of names says some of the descriptions must be correct [Schwartz,SP] |
Full Idea: The traditional theory of proper names entails that at least some combination of the things ordinarily believed of Aristotle are necessarily true of him. | |
From: Stephen P. Schwartz (Intro to Naming,Necessity and Natural Kinds [1977], §III) | |
A reaction: Searle endorses this traditional theory. Kripke and co. tried to dismiss it, but you can't. If all descriptions of Aristotle turned out to be false (it was actually the name of a Persian statue), our modern references would have been unsuccessful. |
10491 | Infinite natural numbers is as obvious as infinite sentences in English [Boolos] |
Full Idea: The existence of infinitely many natural numbers seems to me no more troubling than that of infinitely many computer programs or sentences of English. There is, for example, no longest sentence, since any number of 'very's can be inserted. | |
From: George Boolos (Must We Believe in Set Theory? [1997], p.129) | |
A reaction: If you really resisted an infinity of natural numbers, presumably you would also resist an actual infinity of 'very's. The fact that it is unclear what could ever stop a process doesn't guarantee that the process is actually endless. |
10483 | Mathematics and science do not require very high orders of infinity [Boolos] |
Full Idea: To the best of my knowledge nothing in mathematics or science requires the existence of very high orders of infinity. | |
From: George Boolos (Must We Believe in Set Theory? [1997], p.122) | |
A reaction: He is referring to particular high orders of infinity implied by set theory. Personally I want to wield Ockham's Razor. Is being implied by set theory a sufficient reason to accept such outrageous entities into our ontology? |
10490 | Mathematics isn't surprising, given that we experience many objects as abstract [Boolos] |
Full Idea: It is no surprise that we should be able to reason mathematically about many of the things we experience, for they are already 'abstract'. | |
From: George Boolos (Must We Believe in Set Theory? [1997], p.129) | |
A reaction: He has just given a list of exemplary abstract objects (Idea 10489), but I think there is a more interesting idea here - that our experience of actual physical objects is to some extent abstract, as soon as it is conceptualised. |
10488 | It is lunacy to think we only see ink-marks, and not word-types [Boolos] |
Full Idea: It's a kind of lunacy to think that sound scientific philosophy demands that we think that we see ink-tracks but not words, i.e. word-types. | |
From: George Boolos (Must We Believe in Set Theory? [1997], p.128) | |
A reaction: This seems to link him with Armstrong's mockery of 'ostrich nominalism'. There seems to be some ambiguity with the word 'see' in this disagreement. When we look at very ancient scratches on stones, why don't we always 'see' if it is words? |
10487 | I am a fan of abstract objects, and confident of their existence [Boolos] |
Full Idea: I am rather a fan of abstract objects, and confident of their existence. Smaller numbers, sets and functions don't offend my sense of reality. | |
From: George Boolos (Must We Believe in Set Theory? [1997], p.128) | |
A reaction: The great Boolos is rather hard to disagree with, but I disagree. Logicians love abstract objects, indeed they would almost be out of a job without them. It seems to me they smuggle them into our ontology by redefining either 'object' or 'exists'. |
10489 | We deal with abstract objects all the time: software, poems, mistakes, triangles.. [Boolos] |
Full Idea: We twentieth century city dwellers deal with abstract objects all the time, such as bank balances, radio programs, software, newspaper articles, poems, mistakes, triangles. | |
From: George Boolos (Must We Believe in Set Theory? [1997], p.129) | |
A reaction: I find this claim to be totally question-begging, and typical of a logician. The word 'object' gets horribly stretched in these discussions. We can create concepts which have all the logical properties of objects. Maybe they just 'subsist'? |
3914 | Language arranges sensory experience to form a world-order [Whorf] |
Full Idea: Language first of all is a classification and arrangement of the stream of sensory experience which results in a certain world-order. | |
From: Benjamin Lee Whorf (Punctual and segmentive Hopi verbs [1936], p.55) | |
A reaction: This is only true to a limited degree. See Davidson's 'On the very idea of a conceptual scheme'. All humans share a world-order, to some extent. |
5826 | The intension of "lemon" is the conjunction of properties associated with it [Schwartz,SP] |
Full Idea: The conjunction of properties associated with a term such as "lemon" is often called the intension of the term "lemon". | |
From: Stephen P. Schwartz (Intro to Naming,Necessity and Natural Kinds [1977], §II) | |
A reaction: The extension of "lemon" is the set of all lemons. At last, a clear explanation of the word 'intension'! The debate becomes clear - over whether the terms of a language are used in reference to ideas of properties (and substances?), or to external items. |