als.

Condorcet distinguished ten periods of civilisation, of which the tenth
lies in the future, but he has not justified his divisions and his
epochs are not co-ordinate in importance. Yet his arrangement of the map
of history is remarkable as an attempt to mark its sections not by great
political changes but by important steps in knowledge. The first three
periods--the formation of primitive societies, followed by the pastoral
age, and the agricultural age--conclude with the invention of alphabetic
writing in Greece. The fourth is the history of Greek thought, to the
definite division of the sciences in the time of Aristotle. In the fifth
knowledge progresses and suffers obscuration under Roman rule, and the
sixth is the dark age which continues to the time of the Crusades. The
significance of the seventh period is to prepare the human mind for the
revolution which would be achieved by the invention of printing, with
which the eighth period opens. Some of the best pages of the book
develop the vast consequences of this invention. The scientific
revolution effected by Descartes begins a new period, which is now
closed by the creation of the French Republic.

The idea of the progress of knowledge had created the idea of social
Progress and remained its foundation. It was therefore logical and
inevitable that Condorcet should take advance in knowledge as the clew
to the march of the human race. The history of civilisation is the
history of enlightenment. Turgot had justified this axiom by formulating
the cohesion of all modes of social activity. Condorcet insists on "the
indissoluble union" between intellectual progress and that of liberty,
virtue, and the respect for natural rights, and on the effect of science
in the destruction of prejudice. All errors in politics and ethics have
sprung, he asserts, from false ideas which are closely connected with
errors in physics and ignorance of the laws of nature. And in the new
doctrine of Progress he sees an instrument of enlightenment which is to
give "the last blow to the tottering edifice of prejudices."

It would not be useful to analyse Condorcet's sketch or dwell on his
obsolete errors and the defects of his historical knowledge. His
slight picture of the Middle Ages reflects the familiar view of all
the eighteenth century philosophers. The only contribution to social
amelioration which he can discover in a period of nearly a millennium
is the abolition of domestic sla