her's mind.

[Sidenote: Role of criticism.]

If these speculative adventures do not turn out well, the scientific man
is free to turn about and become the critic and satirist of his foiled
ambitions. He may exhaust scepticism and withdraw into the citadel of
immediate feeling, yielding bastion after bastion to the assaults of
doubt. When he is at last perfectly safe from error and reduced to
speechless sensibility, he will perceive, however, that he is also
washed clean of every practical belief: he would declare himself
universally ignorant but for a doubt whether there be really anything to
know. This metaphysical exercise is simply one of those "fallings from
us, vanishings, blank misgivings of a creature moving about in worlds
not realised" which may visit any child. So long as the suspension of
judgment lasts, knowledge is surely not increased; but when we remember
that the enemy to whom we have surrendered is but a ghost of our own
evoking, we easily reoccupy the lost ground and fall back into an
ordinary posture of belief and expectation. This recovered faith has no
new evidences to rest on. We simply stand where we stood before we began
to philosophise, only with a better knowledge of the lines we are
holding and perhaps with less inclination to give them up again for no
better reason than the undoubted fact that, in a speculative sense, it
is always possible to renounce them.

Science, then, is the attentive consideration of common experience; it
is common knowledge extended and refined. Its validity is of the same
order as that of ordinary perception, memory, and understanding. Its
test is found, like theirs, in actual intuition, which sometimes
consists in perception and sometimes in intent. The flight of science is
merely longer from perception to perception, and its deduction more
accurate of meaning from meaning and purpose from purpose. It generates
in the mind, for each vulgar observation, a whole brood of suggestions,
hypotheses, and inferences. The sciences bestow, as is right and
fitting, infinite pains upon that experience which in their absence
would drift by unchallenged or misunderstood. They take note, infer, and
prophesy. They compare prophecy with event; and altogether they
supply--so intent are they on reality--every imaginable background and
extension for the present dream.

FOOTNOTES:

[Footnote A: For instance, in Plato's "Parmenides," where it is shown
that the ideas are not in the m