Graeser I 60
Extension/Quine/Graeser: when bachelor/unmarried man are coextensive, then why are they not just randomly empirically (contingent) - not sure if it is a matter of meaning.
Lauener XI 175
Reference/Extension/singular term/general term/Follesdal/Lauener: singular terms: have a reference - general terms and sentences have an extension.
>
Singular Terms/Quine, >
General Terms/Quine.
XII (c) 51
Predicate/co-extensive/extension-equal/coextensiveness/synonymy/Quine: coextensive predicates:
e.g. equilateral/equivalent triangle
E.g. featherless biped/rational creature: It was never clear when to say that the predicates had the same meaning.
Extension: (here = reference) is safe.
Meaning: the intension is uncertain.
Translation indeterminacy: here: across to Extension/Intension.
>
Indeterminacy/Quine, >
Intensions/Quine.
VII (b) 21
Extension/meaning/Quine: e.g. "living creature with heart" - "living creature with kidneys": (general term): same extension, different meaning.
VII (e) 89
Extensionality Principle/Quine:
P1 ((x ‹ y ) › ((y ‹ x) › (x = y)))
that is, a class is determined by its elements.
((s) If x and y are subsets of each other, then they are equal).
VII (f) 115
General Term/predicate/Quine: Predicates are not names of classes. This does not mean that there are not often classes that are associated with predicates without being named by them.
For example, if we are talking about the extension of a general term or predicate:
The class of all things of which the predicate is true.
Thus, the theory of validity appeals to classes but not to the individual statements represented by schemes of quantifier logic (quantificational theory). Example:
(Ex)(x is a dog . x is white)
it does not involve an appeal to an abstract extension of a predicate.
>
Predicates/Quine.
VII (f) 116
Truth values/extension/Quine: even validity and the extension of predicates can be eliminated through truth value tables (truth tables).
For an extensional treatment of nominalism see VII (f) 118 >
Nominalism.
IX 1
Extensionality law: Classes are identical if their elements are the same. This does not apply to attributes! >
Classes/Quine.