The psychological-continuity view 20th- and 21st-century versions of the psychological-continuity view can be regarded as refinements of a theory sometimes ascribed to John Locke: person
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the psychological-continuity view is the single most discussed theory of personal identity during the past century, and in part by the fact that exploration of the historical development of this view will naturally lead us to some of the most significant aspects of the debates on questions (b) and (c) as well.1
2 The psychological-continuity view
20th- and 21st-century versions of the psychological-continuity view can be regarded as refinements of a theory sometimes ascribed to John Locke: personal identity over time obtains by virtue of direct memory links (Locke [1690] 1975)
More precisely, someone existing at time t is identical to someone existing at a later time t* if and only if the latter individual can at t* remember something the former person experienced at t.
While this account has the virtue of simplicity, it also has the vice of
incoher-ence (Reid [1785] 2003, 52) Suppose that, thirty years from now, A remembers
some of my present experiences, and I now remember some of the experiences
B had thirty years ago, but A cannot, thirty years from now, remember any of the
experiences B had thirty years before now The present view then entails that, although I am A and I am B, A is not B But this is out of the question, for two
numerically distinct things cannot be identical to one and the same thing
Philosophers were largely silent on personal identity during the first decades of the 20th century, but in 1941 H P Grice proposed a modified and highly sophis-ticated version of the Lockean view, a version that avoids the above objection (Grice 1941) Grice’s complete account is too complex to summarize here, but one of its most crucial components is its appeal to indirect memory links Personal
identity is preserved just in case there is continuity of memory: a chain of direct memory connections Because, in our example, A remembers experiences that
I have at a time at which I remember B’s experiences, Grice’s view yields that A
is identical with B (and I am A and I am B).
Bishop Butler ([1736] 1975, 100) had accused Locke’s theory of being viciously circular: personal identity over time cannot be understood in terms of memory, for memory conceptually presupposes personal identity over time; we simply do not count someone as remembering an earlier experience unless he himself did have the experience Appealing to indirect memory connections is of no help in answering this objection However, something that does seem to help is the notion
of quasi-memory (Shoemaker 1970) Quasi-memory is just like memory except
that it does not conceptually presuppose (although it allows) identity between the quasi-rememberer of an experience and the individual who had the experi-ence Just as my remembering a certain experience conceptually entails that the experience actually occurred, and caused my memory, so my quasi-remembering
a certain experience conceptually entails that the experience actually occurred, and caused my quasi-memory; by contrast, whereas my remembering a certain
experience conceptually entails that I had the experience, my quasi-remembering
a certain experience does not conceptually entail that I had it There is thus no