Apparently, under the inﬂuence of Descartes, they were mechanistic to begin with, and continued to be so to the end of the seventeenth century; then the first efforts of an infant chemistry made its imprint upon them, but throughout the eighteenth century the vitalist themes are thought to have attained or returned to their privileged status, finally coalescing to form a unitary doctrine that 'vitalism' which in slightly differing forms was professed by Bordeu and Barthez in Montpellier, by Blumenbach in Germany, and by Diderot then Bichat in Paris.