In the spring of 1792 he received the rank of marechal de camp in command of the cavalry in the army of the north; but the influence of the extremists becoming predominant he took indefinite leave of absence, and settled at Auteuil, where, with Condorcet and Cabanis, he devoted himself to scientific studies.
On the motion of Cabanis he was named associate of the Institute in the class of the moral and political sciences.
The society of "ideologists" at Auteuil embraced, besides Cabanis and Tracy, Constantin Francois de Chassebeeuf, Comte de Volney and Dominique Joseph Garat (1749-1833), professor in the National Institute.
In 1808 he was elected a member of the French Academy in place of Cabanis, and in 1832 he was also named a member of the Academy of Moral Sciences on its reorganization.
He pushed the sensualistic principles of Condillac to their last consequences, being in full agreement with the materialistic views of Cabanis, though the attention of the latter was devoted more to the physiological, that of Tracy to the psychological or "ideological" side of man.
Cabanis recognized the Pteroptochidae as a distinct Family, but made it also include Menura (see LYREBIRD), and in 1874 P. L.
To Dr Cabanis we are indebted for the ornithological results of Richard Schomburgh's researches given in the third volume (pp. 662-765) of the latter's Reisen im Britisch-Guiana (8vo, 1848), and then in Leotaud's Oiseaux de file de la Trinidad (8vo, 1866).
Some of the most eminent of them have written scarcely a line on the birds of their own country, as Cabanis (editor since 1853 of the Journal fiir Ornithologie), Finsch, Hartlaub, Prince Max of Wied, A.
Under the vague title of " Ornithologische Notizen " Professor Cabanis of Berlin contributed to the Archiv fiir Naturgeschichte (xiii.
In two of the other groups of which Professor Cabanis, especially treated - groups which had been hitherto more or less confounded with the Oscines - the number of primaries was invariably ten, and the outermost of them was comparatively large.
This seems to have been made known by Professor Cabanis the preceding year to the Gesellschaft der Naturforschender Freunde (cf.
Perching birds, that is to say, which are neither birds of prey nor pigeons - proposed by Professor Cabanis, was into four " Orders," as follows: - 1.
Those who enjoyed his closest intimacy were the physiologist Cabanis (Madame de Condorcet's brother-in-law), the poet 1Vlanzoni, the publicist Benjamin Constant, and Guizot.
2 So Lesson called the family from the native name in 1831; Cabanis (1847) suggested Acrulocercus.
Thus Karl Christoph Vogt repeated the saying of the French physician Cabanis, " The brain is determined to thought as the stomach is to digestion, or the liver to the secretion of bile," in the form, " Thought stands in the same relation to the brain as the bile to the liver or the urine to the kidneys."
Unconsciously, however, he fell away from the pure Scottish tradition and made concessions both to moderate empiricism and to the French ideologists (Laromiguiere, Cabanis and Destutt de Tracy).
More and.more he learned from Cabanis and Helvetius to see in the will and the passions the determinants of intellectual life, and in the character and the temper the source of theories and beliefs.