- In their debate about personal identity, Derek Parfit1 ("Parfit (Derek) - Personal Identity", 1971) thinks that our common sense notion of personal identity cannot be preserved, since formal identity fails to preserve it in the fission paradox scenario; David Lewis ("Lewis (David) - Survival and Identity", 1976) thinks that it can be preserved with tense-identity, according to which two continuant persons C1 and C2 are tense identical at T1 iff they share the same person stages at T1.
- I argue that Lewis’ notion of tense identity falls short of its intended goal to capture our common sense notion of personal identity, which is committed to numerical identity, not mere qualitative identity.
- Whereas for Lewis, two continuant persons C1 and C2 are prima facie numerically identical insofar as they are indiscernible, sharing the same person-stages, this indiscernibility relation between C1 and C2 only makes them qualitatively identical, rather than actually numerically identical.
Text Colour Conventions (see disclaimer)
- Blue: Text by me; © Theo Todman, 2019
- Mauve: Text by correspondent(s) or other author(s); © the author(s)