It is not altogether difficult to account for this difference.

When we look at a naked wall, from the evenness of the object, the eye runs along its whole space, and arrives quickly at its termination; the eye meets nothing which may interrupt its progress; but then it meets nothing which may detain it a proper time to produce a very great and lasting effect.

The view of a bare wall, if it be of a great height and length, is undoubtedly grand; but this is only _one_ idea, and not a _repetition_ of _similar_ ideas: it is therefore great, not so much upon the principle of _infinity_, as upon that of _vastness_.

But we are not so powerfully affected with any one impulse, unless it be one of a prodigious force indeed, as we are with a succession of similar impulses; because the nerves of the sensory do not (if I may use the expression) acquire a habit of repeating the same feeling in such a manner as to continue it longer than its cause is in action; besides, all the effects which I have attributed to expectation and surprise in Sect.

11, can have no place in a bare wall.
SECTION XIV.
LOCKE'S OPINION CONCERNING DARKNESS CONSIDERED.
It is Mr.Locke's opinion, that darkness is not naturally an idea of terror; and that, though an excessive light is painful to the sense, the greatest excess of darkness is no ways troublesome.