[Footnote: Condorcet, Esquisse, p.

206 (ed.

1822).] The views of the individual contributors differed greatly, and they cannot be called a school, but they agreed so far in common tendencies that they were able to form a co-operative alliance.
The propaganda of which the Encyclopaedia was the centre was reinforced by the independent publications of some of the leading men who collaborated or were closely connected with their circle, notably those of Diderot himself, Baron d'Holbach, and Helvetius.
3.
The optimism of the Encyclopaedists was really based on an intense consciousness of the enlightenment of their own age.

The progressiveness of knowledge was taken as axiomatic, but was there any guarantee that the light, now confined to small circles, could ever enlighten the world and regenerate mankind?
They found the guarantee they required, not in an induction from the past experience of the race, but in an a priori theory: the indefinite malleability of human nature by education and institutions.

This had been, as we saw, assumed by the Abbe de Saint-Pierre.