just before we strike, we are merely remembering what
happened to our arboreal ancestors, and which has been
stamped by cerebral changes into the heredity of the
race.

There is nothing strange in this, any more than there
is anything strange in an instinct. An instinct is
merely a habit that is stamped into the stuff of our
heredity, that is all. It will be noted, in passing,
that in this falling dream which is so familiar to you
and me and all of us, we never strike bottom. To
strike bottom would be destruction. Those of our
arboreal ancestors who struck bottom died forthwith.
True, the shock of their fall was communicated to the
cerebral cells, but they died immediately, before they
could have progeny. You and I are descended from those
that did not strike bottom; that is why you and I, in
our dreams, never strike bottom.

And now we come to disassociation of personality. We
never have this sense of falling when we are wide
awake. Our wake-a-day personality has no experience of
it. Then--and here the argument is irresistible--it
must be another and distinct personality that falls
when we are asleep, and that has had experience of such
falling--that has, in short, a memory of past-day race
experiences, just as our wake-a-day personality has a
memory of our wake-a-day experiences.

It was at this stage in my reasoning that I began to