rs him in
business or professional success, and puts him at a disadvantage in
every relation of life. On the other hand, a good memory is an asset on
which the owner realizes anew each succeeding day.

1. THE NATURE OF MEMORY

Now that you come to think of it, you can recall perfectly well that
Columbus discovered America in 1492; that your house is painted white;
that it rained a week ago today. But where were these once-known facts,
now remembered so easily, while they were out of your mind? Where did
they stay while you were not thinking of them? The common answer is,
"Stored away in my memory." Yet no one believes that the memory is a
warehouse of facts which we pack away there when we for a time have no
use for them, as we store away our old furniture.

WHAT IS RETAINED.--The truth is that the simple question I asked you is
by no means an easy one, and I will answer it myself by asking you an
easier one: As we sit with the sunlight streaming into our room, where
is the darkness which filled it last night? And where will all this
light be at midnight tonight? Answer these questions, and the ones I
asked about your remembered facts will be answered. While it is true
that, regardless of the conditions in our little room, darkness still
exists wherever there is no light, and light still exists wherever there
is no darkness, yet for this particular room _there is no darkness when
the sun shines in_, and _there is no light when the room is filled with
darkness_. So in the case of a remembered fact. Although the fact that
Columbus discovered America some four hundred years ago, that your house
is of a white color, that it rained a week ago today, exists as a fact
regardless of whether your minds think of these things at all, yet the
truth remains as before: for the particular mind which remembers these
things, _the facts did not exist while they were out of the mind_.

_It is not the remembered fact which is retained_, BUT THE POWER TO
REPRODUCE THE FACT WHEN WE REQUIRE IT.

THE PHYSICAL BASIS OF MEMORY.--The power to reproduce a once-known fact
depends ultimately on the brain. This is not hard to understand if we go
back a little and consider that brain activity was concerned in every
perception we have ever had, and in every fact we have ever known.
Indeed, it was through a certain neural activity of the cortex that you
were able originally to know that Columbus discovered America, that your
house is white, and t