ut shall
seek other characteristics by which a perspective or biography may be
defined.

When (for example) we see one man and hear another speaking at the
same time, what we see and what we hear have a relation which we
can perceive, which makes the two together form, in some sense, one
experience. It is when this relation exists that two occurrences become
associated. Semon's "engram" is formed by all that we experience at one
time. He speaks of two parts of this total as having the relation of
"Nebeneinander" (M. 118; M.E. 33 ff.), which is reminiscent of Herbart's
"Zusammen." I think the relation may be called simply "simultaneity." It
might be said that at any moment all sorts of things that are not part
of my experience are happening in the world, and that therefore the
relation we are seeking to define cannot be merely simultaneity.
This, however, would be an error--the sort of error that the theory
of relativity avoids. There is not one universal time, except by an
elaborate construction; there are only local times, each of which may
be taken to be the time within one biography. Accordingly, if I am (say)
hearing a sound, the only occurrences that are, in any simple sense,
simultaneous with my sensation are events in my private world, i.e. in
my biography. We may therefore define the "perspective" to which
the sensation in question belongs as the set of particulars that are
simultaneous with this sensation. And similarly we may define the
"biography" to which the sensation belongs as the set of particulars
that are earlier or later than, or simultaneous with, the given
sensation. Moreover, the very same definitions can be applied to
particulars which are not sensations. They are actually required for the
theory of relativity, if we are to give a philosophical explanation
of what is meant by "local time" in that theory The relations of
simultaneity and succession are known to us in our own experience;
they may be analysable, but that does not affect their suitability for
defining perspectives and biographies. Such time-relations as can be
constructed between events in different biographies are of a different
kind: they are not experienced, and are merely logical, being designed
to afford convenient ways of stating the correlations between different
biographies.

It is not only by time-relations that the parts of one biography are
collected together in the case of living beings. In this case there are
the mnemi