On page 410 of the last number of _The Monist_, it was stated that the
doctrine of the three stages of knowledge was not properly a Comtean idea
but belonged to Turgot. The following letter from Professor Schaarschmidt
of Bonn informs us of the passages in Turgot where the statement of the
doctrine is found:
_To the Editor of The Monist_:
To your note of inquiry of the 22d of last month I have the
honor to reply, that the Comtean theory of the _trois états_
may be traced back to utterances of Turgot made by him in his
_Second discours sur les progrès successifs de l’esprit humain
prononcé le 2me décembre 1750_—namely in the Sorbonne. You will
find the discourse referred to in the edition of the works of
Turgot which I now have before me, namely that of Guillaumin,
Paris, 1844, in Vol. II, at pages 597 et seqq. The passage in
question is found at p. 600-601. However, it is highly probable
that the so-called _loi des trois états_ was _directly_
transmitted to Comte by St. Simon, who reproduced the idea
of Turgot in his _Introduction aux travaux scientifiques du
XIXme Siècle_, at pages 62-63. For Comte was dependent in many
respects on St. Simon, while it is probable that he had never
studied Turgot. To St. Simon, in fact, is due the expression
“philosophie positive,” as well as the germ-notion of the
division of the Sciences, which Comte further elaborated.