|Indexicality, philosophy of language: Expressions and statements that relate to a situation and its context are indexical. They require a closer determination to enable the attribution of truth values (true, false).|
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indexical properties: different - e.g. property "P": "reflexive to be self-refering" (non-indexical) - e.g. indexical "to be I" - people have all P, but "being I" is different! The (different) indexical properties arise from the property P.
Philosophical Explanations Oxford 1981
The Nature of Rationality 1994