of the black art.

Perhaps the first approach to a correct method was that of
Archimedes, who by much thinking worked out the law of the lever,
reached the conception of the centre of gravity, and demonstrated
the first principles of hydrostatics. It is remarkable that he did
not extend his researches into the phenomena of motion, whether
spontaneous or produced by force. The stationary condition of the
human intellect is most strikingly illustrated by the fact that
not until the time of Leonardo was any substantial advance made on
his discovery. To sum up in one sentence the most characteristic
feature of ancient and medieval science, we see a notable contrast
between the precision of thought implied in the construction and
demonstration of geometrical theorems and the vague indefinite
character of the ideas of natural phenomena generally, a contrast
which did not disappear until the foundations of modern science
began to be laid.

We should miss the most essential point of the difference between
medieval and modern learning if we looked upon it as mainly a
difference either in the precision or the amount of knowledge. The
development of both of these qualities would, under any
circumstances, have been slow and gradual, but sure. We can hardly
suppose that any one generation, or even any one century, would
have seen the complete substitution of exact for inexact ideas.
Slowness of growth is as inevitable in the case of knowledge as in
that of a growing organism. The most essential point of difference
is one of those seemingly slight ones, the importance of which we
are too apt to overlook. It was like the drop of blood in the
wrong place, which some one has told us makes all the difference