by virtue of this
relativity "anthropo-centrism" is restored in a new and more effective
form.

Built out of his own sensations: for the philosophy of Locke was now
triumphant in France. I have used the term Cartesianism to designate,
not the metaphysical doctrines of Descartes (innate ideas, two
substances, and the rest), but the great principles which survived the
passing of his metaphysical system--the supremacy of reason, and the
immutability of natural laws, not subject to providential interventions.
These principles still controlled thought, but the particular views
of Descartes on mental phenomena were superseded in France by the
psychology of Locke, whose influence was established by Voltaire and
Condillac. The doctrine that all our ideas are derived from the senses
lay at the root of the whole theory of man and society, in the light of
which the revolutionary thinkers, Diderot, Helvetius, and their fellows,
criticised the existing order and exposed the reigning prejudices. This
sensationalism (which went beyond what Locke himself had really meant)
involved the strict relativity of knowledge and led at once to the old
pragmatic doctrine of Protagoras, that man is the measure of all things.
And the spirit of the French philosophers of the eighteenth century was
distinctly pragmatic. The advantage of man was their principle, and the
value of speculation was judged by its definite service to humanity.
"The value and rights of truth are founded on its utility," which is
"the unique measure of man's judgements," one thinker asserts; another
declares that "the useful circumscribes everything," l'utile circonscrit
tout; another lays down that "to be virtuous is to be useful; to be
vicious is to be useless or harmful; that is the sum of morality."
Helvetius, anticipating Bentham, works out the theory that utility is
the only possible basis of ethics. Bacon, the utilitarian, was
extolled like Locke. [Footnote: The passages quoted on utility are
from d'Holbach, Systems de la nature, i. c. 12, p. 224; c. 15, p. 312;
Diderot, De I'interpretation de la nature in OEuvres, ii. p. 13; Raynal,
Histoire des deux Indes, vii. p. 416. The effectiveness of the teaching
may be illustrated from the Essay on Man, by Antoine Rivarol, whom Burke
called the Tacitus of the Revolution. "The virtues are only virtues
because they are useful to the human race." OEuvres choisis (ed. de
Lescure), i. p. 211.] As, a hundred years before, his influe