Identity Through Time
Price (Marjorie)
Source: Journal of Philosophy 74, No. 4, Apr., 1977, pp. 201-217
Paper - Abstract

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What follows is a very full account of the paper. My comments appear as footnotes.

  1. The purpose of the paper1 is to attack a doctrine that Price refers to as N, due to three authors:-
    • Geach: a proper name conveys the nominal essence of a common noun, X, such that we can refer to the same X. So, “cat” expresses the nominal essence of the thing we call “Jemima” and Jemima’s corpse2 will be neither Jemima nor a cat (Reference and Generality3, 1962, pp. 43-44)
    • Wiggins: distinguishes between substance and phase sortals4. For a substance sortal5, f, x is no longer f entails x no longer exists, while for a phase sortal6 (eg. “boy”) this is not the case ("Wiggins (David) - Identity & Spatio-temporal Continuity", p. 30).
    • Hirsch: only a few of an object’s properties play a special role in determining the object’s identity – and the corresponding terms are necessary for that identity. ("Hirsch (Eli) - Essence and Identity", p. 33).
  2. So, this doctrine claims that a logically necessary condition for the persistence of a person or a material thing is that some general term or terms (more special than “thing” or “entity”) apply to it throughout the period in question.
  3. Price will argue that the only general terms of which N is true are those – such as “thing” – that trivialise it. It also has implications for essentialism with which N is sometimes confused. However, N only applies to de dicto modalities – but some think that N’s de dicto modalities ground the more controversial de re modalities7.
  4. Price divides “descriptive terms” – those terms that don’t apply to every continuant – into E-terms and A-terms:-
    • An E-term is an essential property of an individual – applicable to it throughout its career if true at all.
    • An A-term is any other general term8.
  5. Price now launches on her TE9 that seeks to disprove N. Consider Rover that falls under the alleged E-terms DOG and TERRIER (as distinct from the A-terms PUPPY, BLACK, etc). Price’s aim is to show that DOG and TERRIER are not in fact E-terms, as Rover can persist when neither apply. The conceit of the TE is that Rover is sent to Mars to determine the effect of the atmosphere on higher animals. On return to Earth, when in quarantine, Rover gradually changes into an amorphous mass of cells – christened “Clover” – even the genetic code of which is unlike that of any other known living thing.
  6. Price takes it as obvious that Clover is Rover. Her claim is that:-
    • Rover has not ceased to exist at any time during the 6 months’ quarantine as “no organism died10” – because Clover is spatio-temporally continuous with Rover, and all the cells are still functioning11 – yet
    • Clover isn’t a DOG (as the only property Clover shares with dogs is being composed of cells – and even those aren’t dog-like cells).
  7. She firstly considers a rather feeble response – that the property “once having been a dog” qualifies Clover as a dog. This, she says “begs the question12 as to the E-term character of DOG”. Since this won’t do, she claims we have an example of a thing that was a DOG at one time of its existence and not a DOG at another.
  8. Price thinks that the most likely response of the N-advocate would be to claim that we have a case of metamorphosis13, on which the TE is modelled. So, we have just discovered that dogs can exist in two radically different forms. The parallel example is of Conger Eel14. It just so happens that or knowledge has increased, and the use for terms like DOG has widened.
  9. Price has two objections to this being a case of metamorphosis15:-
    • 1. The transition in the TE isn’t part of a dog’s normal development, and
    • 2. The individual’s genetic make-up differs pre- and post- the supposed metamorphosis16.
  10. The reasoning behind the first objection is that metamorphosis17 normally occurs in an orderly manner, with the final form being the one that reproduces. In this case the dog might have been of reproductive age18
  11. The reasoning behind the second objection is that
  12. … to be completed.



In-Page Footnotes

Footnote 1: Price thanks Milton Munitz and Peter Unger for assistance.

Footnote 2: Note Wiggins’s (correct) take on the corpse problem.

Footnote 3: Check out"Geach (Peter) - Reference and Generality: Prefaces and Analytical TOC" and "Geach (Peter) - Reference and Generality (Selections)".

Footnote 4: For sortals in general - Click here for Note, and for phase sortals - Click here for Note.

Footnote 7: We are referred to "Bennett (Daniel) - Essential Properties" and to Hirsch’s unpublished PhD Thesis. I ought to cover the de re / de dicto distinction under modality generally – Click here for Note. I don’t understand Price’s point here, and need to follow it up. Maybe "Plantinga (Alvin) - De Re et De Dicto" is a good place to start?

Footnote 8: I’m not clear why it’s called “A”.

Footnote 9: For TEs – Thought Experiments - Click here for Note. This TE was referenced in "Wilson (Jack) - Beyond Horses and Oak Trees: A New Theory of Individuation for Living Entities".

Footnote 10: Price seems to make an egregious error here – confusing the life of the cells with the life of the dog. Surely the dog did die at some time (when it’s heart or brain stopped functioning, whatever the criteria for dog-death happen to be). I don’t think there’s any sorites problem here – at least no more than in any normal case of death. The correct way of describing this situation is probably that at one time a bunch of cells mereologically constitute one thing (a DOG), and later constitute another (a BLOB?). Of course, the TE is somewhat underspecified.

Footnote 11: As noted, this is irrelevant – the dog is no longer functioning. This confuses an organism with a mass of cells. In the normal course of events, many of the cells of a dead dog continue to live for a while. We might also ask whether specific chromosomes are essential properties of cells, but I don’t think they are, and it’s not relevant to the TE in any case.

Footnote 12: I’m not sure about the question-begging, but it’s true that predicates such as F = “once having been an x” do seem to imply “once an F, always an F”, ie. it’s a property a thing can’t lose. But it’s true of any property x, so undermines the distinction between E- and A- terms. That is, whether or not x is an E-term, F is an E-term, and (since the claim here is that being an F makes you an x) if anything that ever was an x is always an x, whatever x might be, then all properties are E-terms.

Footnote 13: For metamorphosis, Click here for Note. I doubt, even if this is indeed a case of metamorphosis, that it is of the identity-preserving kind. Note that a “thing” can undergo a process – eg. death – that it doesn’t survive. So, maybe, a thing can fail to survive a process of metamorphosis.

Footnote 14: "Wiggins (David) - Identity & Spatio-temporal Continuity", p. 59 is cited.

Footnote 18:

Text Colour Conventions (see disclaimer)

  1. Blue: Text by me; © Theo Todman, 2018



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