The new forms taken by the sciences of nature have not been neglected either; and though it is true that Lamarck, by the inﬂuence of a retrospective illusion, has been overestimated at the expense of Cuvier, though it is true that there is little awareness of the fact that 'life' reached the threshold of its positivity for the first time with the Le ons d'anatomie compar, there is nevertheless at least a diffused consciousness of the fact that Western culture began, from that moment onward, to look at the world of living beings with new eyes.