This article demonstrates that identity is not a homogenous phenomenon.Identity statements of the form 'a = b' generally mean that the concept (or the Fregean sense) expressed by the term 'a' and the concept expressed by the term 'b' determine the same reference.When 'a' is a one-criterion term (e.g.'A fortnight is a period of fourteen days.'),one can be competent with the concept expressed by 'a' only if one is competent with the concept expressed by 'b'.This relation is made possible by the coreference de jure between the two concepts, i.e. the synonymy between the corresponding general terms.When 'a' is a cluster term (e.g.'Arthritis is a rheumatoid disease of the joints only.'),one can be minimally competent with the concept expressed by 'a' without being normally competent with the concept expressed by 'b'.This relation is made possible by the coreference de facto between the two concepts.Regarding cluster concepts, we must distinguish minimal competence and normal competence.Natural kind terms are a subclass of cluster terms.When 'a' is a natural kind term (e.g.'Water' is H2O.'), one can be normally competent with the concept expressed by 'a' without being minimally competent with the concept expressed by 'b'.It follows from these considerations that the statement 'a fortnight is a period of fourteen days' is both metaphysically and epistemically necessary (i.e. a priori), 2 b.Phosphorus is Phosphorus.c. Hesperus is Hesperus.'Phosphorus' and 'Phosphorus, or 'Hesperus' and 'Hesperus', are coreferential de jure, whereas 'Phosphorus' and 'Hesperus' are merely coreferential de facto (Pinillos 2011, 2020: 187, Recanati 2016, 2020: 179, 2021, 2024).In Fine's (2007) words, (1b) and (1c) represent the objects in question as the same, whereas (1a) represents them as being the same:The idea of representing objects as the same is to be distinguished from the idea of representing the objects as being the same.The sentences "Cicero = Tully" and "Cicero = Cicero" both represent the objects as being the same but only the second represents them as the same.And, in general, one cannot informatively represent objects as being the same compatibly with representing them as the same.(Fine 2007: 40) In (1b-c) but not in (1a) "it is somehow part of how the names represent their objects that the objects should be the same" (Fine 2007: 39-40) 2 .Put differently, the relevant terms are (positively) coordinated in (1b-c) 3 .Any speaker who understands the expressions 'Phosphorus' and 'Hesperus' is supposed to understand the truthfulness of (1b-c).Knowledge of coreference de jure belongs to grammar, i.e. linguistic competence 4 : a good test of when an object is represented as the same is in terms of whether one might sensibly raise the question of whether it is the same.An object is represented as the same in a piece of discourse only if no one who understands the discourse can sensibly raise the question of whether it is the same.Suppose that you say 'Cicero is an orator' and later say 'Cicero was honest', intending to make the very same use of the name 'Cicero'.Then anyone who raises the question of whether 2 Fine observes that, in order for objects to be represented as being the same, two coreferential expressions must occur in a single sentence:A further difference is that only a single sentence (such as "Cicero = Tully") can represent its objects as being the same but two different sentences (e.g., "Cicero is Roman," "Cicero is an orator") can represent their objects as the same.(Fine 2007: 40) This does not preclude the possibility that two expressions may be coreferential de jure in a single sentence, as in (1b-c).3 Coordination is "the very strongest relation of synonymy or being semantically the same" (Fine 2007: 5) and it does the work of "sameness of sense" (Fine 2007: 60, Lawlor 2010: 493).Although Fine claims that the notion of coordination, a form of strict coreference as opposed to accidental coreference (Fine 2007: 108), should replace the Fregean notion of sense (ibid.: 83-85), Lawlor (2010) argues that coordination or strict coreference cannot be a semantically primitive notion insofar as strict coreference entails coreference (Fine 2007: 45).What Lawlor refers to as 'internal coreference' can hold "among token expressions in thought and language, with no implication of successful reference" (Lawlor 2010: 493).Internal coreference without actual reference, Lawlor says, can be handled by the notion of sense but not by the notion of strict coreference.Ratten (2009: 5) suggests that Fine's position "is not an alternative to Fregean sense, but an elaboration of it". 4 Putnam (1954: 118) claimed that sentences of the form 'a is b' have a different logical structure from sentences of the form 'a is a', even for those who know the identity between the references of 'a' and 'b'.According to Fine (2007: 41), this means that for Putnam the difference between 'a is b' and 'a = a' is "pre-semantic", in that "it is only once the logical form or 'syntax' of the sentences has been determined that the question of semantics comes into play".For Fine, the presence or absence of (positive) coordination between terms is a matter of semantics.Bonardi (2019, 2020: Section 6) objects that coordination should rather be characterized as a non-semantic and subjective notion, because, intuitively, for those speakers who have absolutely no doubt that 'Phosphorus' and 'Hesperus' corefer, these two terms are (positively) coordinated.I shall not go into the matter in this article.
Tomohiro Sakai (Fri,) studied this question.