Occasional Identity
Gallois (Andre)
Source: Philosophical Studies Vol. 58.3: March 1990, pp. 203-224
Paper - Abstract

Paper StatisticsBooks / Papers Citing this PaperNotes Citing this PaperColour-ConventionsDisclaimer


Author’s Abstract

  1. Can distinct things ever be identical? An affirmative answer to this question confirms what I will call the occasional identity1 thesis.
  2. According to OIT it is possible for there to exist something which is identical at some time with something it is distinct from at another.
  3. In this paper I propose to defend OIT against the charge that it violates a fundamental principle governing identity known as Leibniz's Law2.
  4. Is OIT worth defending? It is if only because it reconciles conflicting intuitions about imaginable cases.
  5. Perhaps the most extensively discussed case is one in which a person putatively divides into distinct persons.
    1. It seems possible for an individual Jones to survive the destruction of the left hemisphere of his brain, and for there to be a later individual who results from the transplantation3 of the remaining hemisphere into some suitably debrained body.
    2. It likewise seems possible, subsequent to the destruction of the right hemisphere of Jones's brain, for an individual to result from the transplantation4 of the remaining hemisphere into some other debrained body.
  6. Call the individual who results from the transplantation5 of Jones's right hemisphere the right-hand survivor, and the individual who results from the transplantation6 of Jones's left hemisphere the left-hand survivor.
    1. In the absence of the left-hand survivor it is intuitively compelling to identify Jones with the right-hand survivor.
    2. In the absence of the right-hand survivor it is intuitively compelling to identify Jones with the left-hand survivor.
  7. What should we say if both the right-hand and left-hand survivors are on the scene together after the operation?

Text Colour Conventions (see disclaimer)

  1. Blue: Text by me; © Theo Todman, 2018
  2. Mauve: Text by correspondent(s) or other author(s); © the author(s)



© Theo Todman, June 2007 - Dec 2018. Please address any comments on this page to theo@theotodman.com. File output:
Website Maintenance Dashboard
Return to Top of this Page Return to Theo Todman's Philosophy Page Return to Theo Todman's Home Page