al things.

While physical things, namely, are supposed to be permanent and to have
their 'states,' a fact of consciousness exists but once and _is_ a
state. Its _esse_ is _sentiri_; it is only so far as it is felt; and it
is unambiguously and unequivocally exactly _what_ is felt. The
hypothesis under consideration would, however, oblige it to be felt
equivocally, felt now as part of my mind and again at the same time
_not_ as a part of my mind, but of yours (for my mind is _not_ yours),
and this would seem impossible without doubling it into two distinct
things, or, in other words, without reverting to the ordinary dualistic
philosophy of insulated minds each knowing its object representatively
as a third thing,--and that would be to give up the pure-experience
scheme altogether.

Can we see, then, any way in which a unit of pure experience might enter
into and figure in two diverse streams of consciousness without turning
itself into the two units which, on our hypothesis, it must not be?

II

There is a way; and the first step towards it is to see more precisely
how the unit enters into either one of the streams of consciousness
alone. Just what, from being 'pure,' does its becoming 'conscious'
_once_ mean?

It means, first, that new experiences have supervened; and, second, that
they have borne a certain assignable relation to the unit supposed.
Continue, if you please, to speak of the pure unit as 'the pen.' So far
as the pen's successors do but repeat the pen or, being different from
it, are 'energetically'[70] related to it, it and they will form a group
of stably existing physical things. So far, however, as its successors
differ from it in another well-determined way, the pen will figure in
their context, not as a physical, but as a mental fact. It will become a
passing 'percept,' _my_ percept of that pen. What now is that decisive
well-determined way?

In the chapter on 'The Self,' in my _Principles of Psychology_, I
explained the continuous identity of each personal consciousness as a
name for the practical fact that new experiences[71] come which look
back on the old ones, find them 'warm,' and greet and appropriate them
as 'mine.' These operations mean, when analyzed empirically, several
tolerably definite things, viz.:

1. That the new experience has past time for its 'content,' and in that
time a pen that 'was';

2. That 'warmth' was also about the pen, in the sense of a group of
feelings ('i