2. Scientific Revolutions.
Scientific revolutions are by far the most important.
Although they attract but little attention, they are often
fraught with remote consequences, such as are not engendered by
political revolutions. We will therefore put them first,
although we cannot study them here.
For instance, if our conceptions of the universe have
profoundly changed since the time of the Revolution, it is
because astronomical discoveries and the application of
experimental methods have revolutionised them, by demonstrating
that phenomena, instead of being conditioned by the caprices of
the gods, are ruled by invariable laws.
Such revolutions are fittingly spoken of as evolution, on
account of their slowness. But there are others which, although
of the same order, deserve the name of revolution by reason of
their rapidity: we
his instance the theories of Darwin, overthrowing the whole
science of biology in a few years; the discoveries of Pasteur,
which revolutionised medicine during the lifetime of their
author; and the theory of the dissociation of matter, proving
that the atom, formerly supposed to be eternal, is not immune
from the laws which condemn all the elements of the universe to
decline and perish.
These scientific revolutions in the domain of ideas are
purely intellectual. Our sentiments and beliefs do not affect
them. Men submit to them without discussing them. Their results
being controllable by experience, they escape all criticism.
