witty sallies for which the princes of science are so justly famed and
to which they often treat us even when they are not in the presence of
works of art, had not the professor followed up his clue with the utmost
gravity, assuring me at last that no picture in the gallery was beyond
the reach of optical diagnostic. Still suspicious of his good faith, I
suggested, tentatively, that perhaps the discrepancies between the
normal man's vision and the pictures on the wall were the result of
intentional distortion on the part of the artists. At this the professor
became passionately serious--"Do you mean to tell me," he bawled, "that
there has ever been a painter who did not try to make his objects as
lifelike as possible? Dismiss such silly nonsense from your head." It is
the old story: "Clear your mind of cant," that is to say, of anything
which appears improbable or unpalatable to Dr. Johnson.

The religious, on the other hand, are apt to be a little prejudiced
against common-sense; and, for my own part, I confess that I am often
tempted to think that a common-sense view is necessarily a wrong one. It
was common-sense to see that the world must be flat and that the sun
must go round it; only when those fantastical people made themselves
heard who thought that the solar system could not be quite so simple an
affair as common-sense knew it must be were these opinions knocked on
the head. Dr. Johnson, the great exemplar of British common-sense,
observing in autumn the gathered swallows skimming over pools and
rivers, pronounced it certain that these birds sleep all the winter--"A
number of them conglobulate together, by flying round and round, and
then all in a heap throw themselves under water, and lie in the bed of a
river": how sensibly, too, did he dispose of Berkeley's
Idealism--"striking his foot with mighty force against a large
stone"--"I refute it thus." Seriously, is the common-sense view ever the
right one?