eathenism against
Christianity;(998) the second, the reawakening of free thought in the
middle ages;(999) the third, that which appertained to the revival of
classical literature;(1000) the fourth, to the growth of modern
philosophy;(1001)--a series of epochs which exhibit the struggle of
Christianity in the great centres of thought and civilization, ancient or
modern; and it was proposed that our investigation should not only contain
a chronicle of the facts, but explain the causes, and teach the
moral.(1002) We considered that the causes which make thought develope
into unbelief are chiefly two,--the emotional and the intellectual;(1003)
and, while vindicating distinctness of operation for the intellectual
under certain circumstances,(1004) yet we allowed the union of them with
the moral to be so intimate,(1005) that not only must account always be
taken of the latter in estimating the unbelief of individuals, but the
exclusive study of the former, without allowing for the existence of the
latter, must be regarded as likely to lead to an imperfect and injurious
idea of unbelief.

The intellectual causes were however selected as the special subject of
our study;(1006) partly because they have been much neglected by Christian
writers, partly because they are the forms which for the most part create
the doubts which Christians encounter in the present age. The principal
intellectual causes were considered(1007) to be, either the new material
of knowledge, such as the physical or metaphysical sciences, which may
present truth antagonistic to the teaching of the sacred literature; or
new methods of criticism, the application of which creates opinions
differing from those of the traditionary belief; and, above all, the
effects of the application of particular tests of truth,--sense, reason,
intuition, feeling,--to the doctrines of revealed religion.

This was our plan; and we have been employed in tracing the influence of
these causes in generating doubt in the four great crises, with a
minuteness which may almost have been tedious; endeavouring to supply the
natural as well as the literary history; analysing each successive step of
thought into the causes which produced it; searching for them when
necessary in the intellectual biography of individuals; and, if not
refuting results, at least laying bare by criticism the processes through
which they were attained. At the same time we have attempted to show the
grounds on wh