he field of vision; whereas the abstraction of the poet is meant
to bring the object itself into more vivid relief, to make it visible
by means of the selected qualities. In other words, the one aims at
abstract symbols, the other at picturesque effects. The one can carry
on his deductions by the aid of colourless signs, X or Y. The other
appeals to the emotions through the symbols which will most vividly
express the real objects in their relations to our sensibilities.

Imagination is obviously active in both. From known facts the
philosopher infers the facts that are unapparent. He does so by an
effort of imagination (hypothesis) which has to be subjected to
verification: he makes a mental picture of the unapparent fact, and
then sets about to prove that his picture does in some way correspond
with the reality. The correctness of his hypothesis and verification
must depend on the clearness of his vision. Were all the qualities of
things apparent to Sense, there would be no longer any mystery. A
glance would be Science. But only some of the facts are visible; and it
is because we see little, that we have to imagine much. We see a
feather rising in the air, and a quill, from the same bird, sinking to
the ground: these contradictory reports of sense lead the mind astray;
or perhaps excite a desire to know the reason. We cannot see,--we must
imagine,--the unapparent facts. Many mental pictures may be formed, but
to form the one which corresponds with the reality requires great
sagacity and a very clear vision of known facts. In trying to form this
mental picture we remember that when the air is removed the feather
fails as rapidly as the quill, and thus we see that the air is the
cause of the feather's rising; we mentally see the air pushing under
the feather, and see it almost as plainly as if the air were a visible
mass thrusting the feather upwards.

From a mistaken appreciation of the real process this would by few be
called an effort of Imagination. On the contrary some "wild hypothesis"
would be lauded as imaginative in proportion as it departed from all
suggestion of experience, i.e. real mental vision. To have imagined
that the feather rose owing to its "specific lightness," and that the
quill fell owing to its "heaviness," would to many appear a more
decided effort of the imaginative faculty. Whereas it is no effort of
that faculty at all; it is simply naming differently the facts it
pretends to explain. To imag