there. Of these
you weave together those which are the most useful, the most
obvious, the most often repeated: which make a tidy and coherent
pattern when seen on the right side. Shut up with this symbolic
picture, you soon drop into the habit of behaving to it as though it
were not a representation but a thing. On it you fix your attention;
with it you "unite." Yet, did you look at the wrong side, at the
many short ends, the clumsy joins and patches, this simple
philosophy might be disturbed. You would be forced to acknowledge
the conventional character of the picture you have made
so cleverly, the wholesale waste of material involved in the
weaving of it: for only a few amongst the wealth of impressions
we receive are seized and incorporated into our picture of the
world. Further, it might occur to you that a slight alteration in the
rhythm of the senses would place at your disposal a complete
new range of material; opening your eyes and ears to sounds,
colours, and movements now inaudible and invisible, removing
from your universe those which you now regard as part of the
established order of things. Even the strands which you have
made use of might have been combined in some other way; with
disastrous results to the "world of common sense," yet without
any diminution of their own reality.

Nor can you regard these strands themselves as ultimate. As the
most prudent of logicians might venture to deduce from a skein
of wool the probable existence of a sheep; so you, from the raw
stuff of perception, may venture to deduce a universe which
transcends the reproductive powers of your loom. Even the
camera of the photographer, more apt at contemplation than the
mind of man, has shown us how limited are these powers in some
directions, and enlightened us as to a few of the cruder errors of
the person who accepts its products at face-value; or, as he would
say, believes his own eyes. It has shown us, for instance, that the
galloping race-horse, with legs stretched out as we are used to see
it, is a mythical animal, probably founded on the mental image or
a running dog. No horse has ever galloped thus: but its real action
is too quick for us, and we explain it to ourselves as something
resembling the more deliberate dog-action which we have caught
and registered as it passed. The plain man's universe is full of
race-horses which are really running dogs: of conventional
waves, first seen in pictures and then imagined upon t