Philosophy Dictionary of ArgumentsHome | |||
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Identity: Two objects are never identical. Identity is a single object, to which may be referred to with two different terms. The fact that two descriptions mean a single object may be discovered only in the course of an investigation._____________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 |
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M.J. Cresswell on Identity - Dictionary of Arguments
I, 117 ff Contingent Identity/some authors: here the Leibniz principle fails. >Leibniz principle. Cresswell: better: that is only apparent identity. E.g. the largest wooden building = the most beautiful building right: the largest wooden necessary wooden - but not necessary identical with the most beautiful. Problem: If it is identical, then it is necessarily indentical. Necessary identity/(s): according to Kripke identity is necessary when names rather than labels are involved. >Identity/Kripke, >Descriptions, >Proper names. I 126 Necessary identity/Cresswell: if morning star = evening star, then: (if morning star and evening star nominal): false: N (morning star x)(evening star y) (x = y) but true: (morning star x)(evening star y)N(x = y). For x = y is true in every world under an attribution V iff V(x) = V(y), and then it is true in every possible world if it is true in one and then N(x = y). Cresswell later: this corresponds in Hughes/Cresswell/HC: "The man next door = the major" as a natural truth: that is unnatural. Cf. >Morning star/Evening star. Hughes I 167f Identity/Hughes/Cresswell: identity is always necessary: (x =) always underlying, even if x appears under different descriptions. The descriptions are contingent, but not the identity of the object with itself - this also applies to non-identity: it is always necessary even if the corresponding sentence is true. >Non-identity._____________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. |
Cr I M. J. Cresswell Semantical Essays (Possible worlds and their rivals) Dordrecht Boston 1988 Cr II M. J. Cresswell Structured Meanings Cambridge Mass. 1984 Hughes I G.E. Hughes Maxwell J. Cresswell Einführung in die Modallogik Berlin New York 1978 |