# Psychology Dictionary of Arguments

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Predicates, philosophy, logic: predicates are symbols that can stand in logical formulas for properties. In fact, not every predicate stands for a property, since it has contradictory predicates, but no contradictory properties. For example, one can think of a predicate "squaround" for "square and round", that is, two properties that exclude each other. One can then truthfully say "Nothing is squaround". There are therefore more predicates than properties. See also round square, scheme characters, quantification, 2nd level logic, predication, attributes, adjectives.

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Annotation: The above characterizations of concepts are neither definitions nor exhausting presentations of problems related to them. Instead, they are intended to give a short introduction to the contributions below. – Lexicon of Arguments.

Author Concept Summary/Quotes Sources

Peter Geach on Predicates - Dictionary of Arguments

I 110
Predicate/Geach: "predicables": spurious predicates are: e.g.m, "--- smoked a pipe" - "5 is dividable by 5 and by one", as well as for "3...".
Predicate: real predicates are: e.g.,"Russell smoked a pipe" - the identity of predicates with reflexive pronouns is not assured.
I 216
Predicate/Geach: a predicate must never be confused with names. - The term does not denote the object.
>Name/Geach, >Objects, >Denotation/Geach.
I 224
Predicates/Geach: more common property of sentences - but not an actual expression in the sentence.
>Sentences/Geach, >Syntax/Geach.
I 224
"Stand for"/Geach: there is no difference whether I say a predicate "stands for" a property or it is its name.
>Proxy.
I 224
Predicate/Geach: a predicate does not appear as an actual expression in the sentence.
Geach: there is no identity criterion for predicates.
>Identity criterion.
One cannot know whether two predicates stand for the same property.
Equality of use is necessary condition for same reference. - ((s) That is, the extension but not the intension is equal.)
>Intension, >Extension, >Language use, >Speaker meaning.
GeachVsQuine: therefore one should not identify properties with classes.
>Properties/Quine.
I 239
Predicate/Terminology/Geach: I call predicates only like this if they are used as the principal functor in a proposition, otherwise "predicables".
I-predicables/I-predicate/Geach/(s): those predicates in which regard the two objects are indistinguishable in a given theory.
If distinctions can be made in an extended theory, then the I-predicate does not change its meaning - E.g. "uniform" for (different but not at all differentiated) tokens of words, later the tokens are distinguished, but are still "uniform".
I 301
GeachVs two-name theory: error: that if two names denote the same thing, that they then allow the same predicates.
>Denotation/Geach, for "two-name-theory" see >Designation/Geach.
I 301
Predicate/Geach: Predicates such as "become" can only be assigned to concrete terms.

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Explanation of symbols: Roman numerals indicate the source, arabic numerals indicate the page number. The corresponding books are indicated on the right hand side. ((s)…): Comment by the sender of the contribution. Translations: Dictionary of Arguments
The note [Concept/Author], [Author1]Vs[Author2] or [Author]Vs[term] resp. "problem:"/"solution:", "old:"/"new:" and "thesis:" is an addition from the Dictionary of Arguments. If a German edition is specified, the page numbers refer to this edition.

Gea I
P.T. Geach
Logic Matters Oxford 1972

> Counter arguments against Geach