Mozley: A Treatise on the Augustinian Doctrine of

CHAP. xi. Conclusion. 297
simple apprehension, or by demonstrative reasoning : the
dark side is that on which it does not perceive in either
of these two ways ; but either does not see at all, and has
a blank before it, or has only an incipient and indistinct
sight, not amounting to perception or apprehension. 1
In
proportion, then, to the acuteness with which the mind
perceives truth, either by apprehension or by demonstra
tion, on its luminous side, in that proportion it sees the
defect of perception on its dark side. The clearness of
knowledge, where it is had, reveals and exposes by the
contrast its absence, where it is not had ; and the transi
tion from light heightens the obscurity. Each successive
step of demonstrative reasoning, by which a problem in
mathematics is proved, from the first up to the conclusion,
is accomplished by means of a certain light contained
within it an overpowering light, to which the mind suc
cumbs, unable to resist its penetrating force, but pierced
through by it, as by lightning. Even that elementary and
primary piece of demonstrative reasoning which is called
an axiom, that first inference or extraction of one truth
from another, which, in the department of demonstration,
we are called upon to make, is accomplished by means
of such a vivid and penetrating light contained within it ;
so that the perception of the simplest axiom, where such
perception is a true and not a formal one, is, by reason of
this perfection of light in it, an illumination for the time
of the whole intellect, and may be regarded as a kind of
natural inspiration, answering to passion
or emotion in
moral life. In proportion, then, to the keenness with which
this process goes on, is the reaction from it ; after the clear
ness of sight the change is all the greater to its dimness
and indistinctness ; and the reason turning, while full of
penetrating light from one side, upon the darkness of the
other, receives, as it were, a shock, by the violence of the
contrast. The difference between seeing truth and not
seeing it, between knowledge and is felt
ignorance,
in a
and manner in which those who have not attained
degree
such sight or knowledge, cannot feel it. The analytical
1 See Chapter II.