e data of past experience, merely one of the
characteristics of the age of illumination?

Voltaire and Montesquieu thus raised fundamental questions of great
moment for the doctrine of Progress, questions which belong to what
was soon to be known as the Philosophy of History, a name invented by
Voltaire, though hardly meant by him in the sense which it afterwards
assumed.

3.

Six years before Voltaire's Essay was published in its complete form a
young man was planning a work on the same subject. Turgot is honourably
remembered as an economist and administrator, but if he had ever written
the Discourses on Universal History which he designed at the age
of twenty-three his position in historical literature might have
overshadowed his other claims to be remembered. We possess a partial
sketch of its plan, which is supplemented by two lectures he delivered
at the Sorbonne in 1750; so that we know his general conceptions.

He had assimilated the ideas of the Esprit des lois, and it is probable
that he had read the parts of Voltaire's work which had appeared in
a periodical. His work, like Voltaire's, was to be a challenge to
Bossuet's view of history; his purpose was to trace the fortunes of the
race in the light of the idea of Progress. He occasionally refers to
Providence but this is no more than a prudent lip-service. Providence
has no functions in his scheme. The part which it played in Bossuet is
usurped by those general causes which he had learned from Montesquieu.
But his systematic mind would have organised and classified the ideas
which Montesquieu left somewhat confused. He criticised the inductions
drawn in the Esprit des lois concerning the influence of climate as
hasty and exaggerated; and he pointed out that the physical causes can
only produce their effects by acting on "the hidden principles which
contribute to form our mind and character." It follows that the
psychical or moral causes are the first element to consider, and it is
a fault of method to try to evaluate physical causes till we have
exhausted the moral, and are certain that the phenomena cannot be
explained by these alone. In other words, the study of the development
of societies must be based on psychology; and for Turgot, as for all his
progressive contemporaries, psychology meant the philosophy of Locke.

General necessary causes, therefore, which we should rather call
conditions, have determined the course of history--the nature of man,