18909
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Aristotelian sentences are made up by one of four 'formative' connectors [Aristotle, by Engelbretsen]
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Full Idea:
For Aristotle there are four formatives for sentences: 'belongs to some', 'belongs to every', 'belongs to no', and 'does not belong to every'. These are 'copulae'. Aristotle would have written 'wise belongs to some man'.
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From:
report of Aristotle (Prior Analytics [c.328 BCE]) by George Engelbretsen - Trees, Terms and Truth 3
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A reaction:
A rather set-theoretic reading. This invites a Quinean scepticism about whether wisdom is some entity which can 'belong' to a person. It makes trope theory sound attractive, offering a unique wisdom that is integrated into that particular person.
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8080
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Aristotelian identified 256 possible syllogisms, saying that 19 are valid [Aristotle, by Devlin]
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Full Idea:
Aristotle identified four 'figures' of argument, based on combinations of Subject (S) and Predicate (P) and Middle term (M). The addition of 'all' and 'some', and 'has' and 'has not' got the property, resulted in 256 possible syllogisms, 19 of them valid.
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From:
report of Aristotle (Prior Analytics [c.328 BCE]) by Keith Devlin - Goodbye Descartes Ch.2
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A reaction:
[Compressed version of Devlin] What Aristotle did was astonishing, and must be one of the key ideas of western civilization, even though a lot of his assumptions have been revised or rejected.
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13912
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Aristotle replaced Plato's noun-verb form with unions of pairs of terms by one of four 'copulae' [Aristotle, by Engelbretsen/Sayward]
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Full Idea:
Aristotle replaced the Platonic noun-verb account of logical syntax with a 'copular' account. A sentence is a pair of terms bound together logically (not necessarily grammatically) by one of four 'logical copulae' (every, none, some, not some).
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From:
report of Aristotle (Prior Analytics [c.328 BCE]) by Engelbretsen,G/Sayward,C - Philosophical Logic: Intro to Advanced Topics 8
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A reaction:
So the four copulas are are-all, are-never, are-sometimes, and are-sometime-not. Consider 'men' and 'mortal'. Alternatively, Idea 18909.
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9403
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There are three different deductions for actual terms, necessary terms and possible terms [Aristotle]
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Full Idea:
Since to belong, to belong of necessity, and to be possible to belong are different, ..there will be different deductions for each; one deduction will be from necessary terms, one from terms which belong, and one from possible terms.
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From:
Aristotle (Prior Analytics [c.328 BCE], 29b29-35)
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A reaction:
Fitting and Mendelsohn cite this as the earliest thoughts on modal logic. but Kneale and Kneale say that Aristotle got into a muddle, and so was unable to create a workable system.
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11148
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Deduction is when we suppose one thing, and another necessarily follows [Aristotle]
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Full Idea:
A deduction is a discourse in which, certain things having been supposed, something different from the things supposed results of necessity because these things are so.
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From:
Aristotle (Prior Analytics [c.328 BCE], 24b18)
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A reaction:
Notice that it is modal ('suppose', rather than 'know'), that necessity is involved, which is presumably metaphysical necessity, and that there are assumptions about what would be true, and not just what follows from what.
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8079
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Aristotelian logic has two quantifiers of the subject ('all' and 'some') [Aristotle, by Devlin]
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Full Idea:
Aristotelian logic has two quantifiers of the subject ('all' and 'some'), and two ways to combine the subject with the predicate ('have', and 'have not'), giving four propositions: all-s-have-p, all-s-have-not-p, some-s-have-p, and some-s-have-not-p.
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From:
report of Aristotle (Prior Analytics [c.328 BCE]) by Keith Devlin - Goodbye Descartes Ch.2
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A reaction:
Frege seems to have switched from 'some' to 'at-least-one'. Since then other quantifiers have been proposed. See, for example, Ideas 7806 and 6068.
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18911
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Linguistic terms form a hierarchy, with higher terms predicable of increasing numbers of things [Aristotle, by Engelbretsen]
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Full Idea:
According to Aristotle, the terms of a language form a finite hierarchy, where the higher terms are predicable of more things than are lower terms.
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From:
report of Aristotle (Prior Analytics [c.328 BCE]) by George Engelbretsen - Trees, Terms and Truth 3
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A reaction:
I would be a bit cautious about placing something precisely in a hierarchy according to how many things it can be predicated of. It is a start, though, in trying to give a decent account of generality, which is a major concept in philosophy.
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3238
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'Dead person' isn't a contradiction, so 'person' is somewhat vague [Williams,B]
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Full Idea:
If we say (in opposition to a physical view of identity) that when Jones dies 'Jones ceases to exist' but 'Jones' body does not cease to exist', this shouldn't be pressed too hard, because it would make 'dead person' a contradiction.
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From:
Bernard Williams (Are Persons Bodies? [1970], p.74)
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A reaction:
A good point, which nicely challenges the distinction between a 'human' and a 'person', but the problem case is much more the one where Jones gets advanced Alzheimer's, rather than dies. A dead body ceases as a mechanism, as well as as a personality.
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3239
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You can only really love a person as a token, not as a type [Williams,B]
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Full Idea:
If you love a person as a type instead of as a token (i.e. a "person", instead of a physical body) you might prefer a run-down copy of them to no person at all, but at this point our idea of loving a person begins to crack.
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From:
Bernard Williams (Are Persons Bodies? [1970], p.81)
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A reaction:
Very persuasive. If you love a person you can cope with them getting old. If you own an original watercolour, you can accept that it fades, but you would replace a reproduction of it if that faded. But what, then, is it that you love?
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