his logical positions are assailable. Never before in France had
materialism, necessarianism and atheism been so clearly and forcibly
expounded. The very Philosophers were alarmed. Voltaire hastened to
write an article on God so unconvincing, that it can hardly have
convinced himself. It amounts to little more than an argument that God
is the most probable of hypotheses, and it admits that there may be two
or several gods as well as one. It is not unlikely that Voltaire thought
it necessary for his peace in the world to protest against so outspoken
a book as the "System of Nature."

The true answer to Holbach is to be found in a different order of ideas
from any that Voltaire was prepared to accept. Yet Locke might have
taught him that if there is no logical reason to believe in the
existence of mind, there is as little to believe in the existence of
matter. Experience might have shown him that men do not always seek the
thing which they believe most useful to themselves. The old and favorite
doctrine of utility labors under the disadvantage that it has never
shown, nor ever can show, an adequate reason why any man should care for
another or for the race. And as for the existence of God,--that can no
more be proved by argument than the existence of matter, mind, or the
_non-ego_.

Helvetius and Holbach had worked out the theories of the school to their
last philosophical conclusion. A younger writer in the last years of the
reign of Louis XV. was to furnish the complete application of them. The
Chevalier de Chastellux is well known in America by the book of travels
which he wrote when he accompanied the Marquis of Rochambeau in the
Revolutionary War. Chastellux was just then at the height of his
reputation. He had published in 1772 a book which, although now almost
forgotten, is still interesting as a link between the thought of the