orld was that it had
both enlightened and propagated _natural religion_.'[37]

[Footnote 37: _Lettres sur la Tolerance_, II. vol. ii. 687.]

III.

Turgot's inquiry into the extent and quality of the debt of European
civilisation to Christianity was marked by a certain breadth and
largeness, in spite of the bonds of circumstance and subject--for who,
after all, can consider Christianity to any purpose, apart from other
conditions of general progress, or without free comparison with other
dogmatic systems? It is not surprising, then, to find the same valuable
gifts of vision coming into play with a thousand times greater liberty
and power, when the theme was widened so as to comprehend the successive
steps of the advancement of the human mind in all its aspects. The
Second and more famous of the two Discourses at the Sorbonne was read in
December 1750, and professes to treat the Successive Advances of the
Human Mind.[38] The opening lines are among the most pregnant, as they
were among the most original, in the history of literature, and reveal
in an outline, standing clear against the light, a thought which
revolutionised old methods of viewing and describing the course of human
affairs, and contained the germs of a new and most fruitful philosophy
of society.

[Footnote 38: Sur les progres successifs de l'esprit humain. _OEuv._
ii. 597-611.]

'The phenomena of nature, subjected as they are to constant laws, are
enclosed in a circle of revolutions that remain the same for ever. All
comes to life again, all perishes again; and in these successive
generations, by which vegetables and animals reproduce themselves, time
does no more than bring back at each moment the image of what it has
just dismissed.

'The succession of men, on the contrary, offers from age to age a
spectacle of continual variations. Reason, freedom, the passions, are
incessantly producing new events. _All epochs are fastened together by a
sequence of causes and effects, linking the condition of the world to
all the conditions that have gone before it._ The gradually multiplied
signs of speech and writing, giving men an instrument for making sure of
the continued possession of their ideas, as well as of imparting them to
others, have formed out of the knowledge of each individual a common
treasure, which generation transmits to generation, as an inheritance
constantly augmented by the discoveries of each age; and the human race,
observed f