With respect to those ideas which relate to the physical world, we
remark, that, though the assimilants required are supplied by
the senses, the senses have in themselves no _productive,
coöperating_ energy, being but the passive instruments, or medium,
through which they are conveyed. That the senses, in this relation,
are merely passive, admits of no question, from the obvious difference
between the idea and the objects. The senses can do no more than
transmit the external in its actual forms, leaving the images in the
mind exactly as they found them; whereas the intuitive power rejects,
or assimilates, indefinitely, until they are resolved into the proper
perfect form. Now the power which prescribes that form must, of
necessity, be antecedent to the presentation of the objects which it
thus assimilates, as it could not else give consistence and unity to
what was before separate or fragmentary. And every one who has
ever realized an idea of the class in which alone we compare the
assimilants with the ideal form, be he poet, painter, or philosopher,
well knows the wide difference between the materials and their result.
When an idea is thus realized and made objective, it affirms its own
truth, nor can any process of the understanding shake its foundation;
nay, it is to the mind an essential, imperative truth, then emerging,
as it were, from the dark potential into the light of reality.

If this be so, the inference is plain, that the relation between the
actual and the ideal is one of necessity, and therefore, also, is the
predetermined correspondence between the prescribed form of an
idea and its assimilant; for how otherwise could the former become
recipient of that which was repugnant or indifferent, when the
presence of the latter constitutes the very condition by which it is
manifested, or can be known to exist? By actual, here, we do not mean
the exclusively physical, but whatever, in the strictest sense, can be