Critique of the Pure Reason', do not properly belong to literature.
(By the "spiritual" I would be understood to mean the whole domain
of the emotional, the susceptible or impressible, the sympathetic,
the intuitive; in short, that mysterious something in the constitution
of man by and through which he holds relationship with
the essential spirit of things, as opposed to the phenomenal
of which the senses take cognizance.)

The term literature is sometimes extended in meaning (and it may be
so extended), to include all that has been committed to letters,
on all subjects. There is no objection to such extension
in ordinary speech, no more than there is to that of the signification
of the word, "beauty" to what is purely abstract. We speak,
for example, of the beauty of a mathematical demonstration;
but beauty, in its strictest sense, is that which appeals to
the spiritual nature, and must, therefore, be concrete, personal,
not abstract. Art beauty is the embodiment, adequate,
effective embodiment, of co-operative intellect and spirit,--
"the accommodation," in Bacon's words, "of the shows of things
to the desires of the mind."

It follows that the relative merit and importance of different periods
of a literature should be determined by the relative degrees
of spirituality which these different periods exhibit.
The intellectual power of two or more periods, as exhibited
in their literatures, may show no marked difference,
while the spiritual vitality of these same periods may
very distinctly differ. And if it be admitted that literature proper
is the product of co-operative intellect and spirit (the latter being
always an indispensable factor, though there can be no high order
of literature that is not strongly articulated, that is not
well freighted, with thought), it follows that the periods
of a literature should be determined by the ebb and flow
of spiritual life which they severally register, rather than
by any other considerations. There are periods which
are characterized by a "blindness of heart", an inactive,
quiescent condition of the spirit, by which the intellect
is more or less divorced from the essential, the eternal,
and it directs itself to the shows of things. Such periods may embody
in their literatures a large amount of thought,--thought which is
conversant with the externality of things; but that of itself
will not constitute a noble literature, however perfect
the forms in which it may be