BOOK IX.
THE
PHILOSOPHY
OF
BIOLOGY.
La vie est donc un Tourbillon plus ou moins rapide, plus ou moins compliqué, dont la direction est constante, et qui entraine toujours des molecules de mêmes sorts, mais où les molecules individuelles entrent et d’où elles sortent continuellement, de manière que la Forme du corps vivant lui est plus essentielle que sa Matière.
Tant que ce mouvement subsiste, le corps où il s’exerce est vivant; il vit. Lorsque le mouvement s’arrête sans retour, le corps meurt.
Cuvier, Règne Animal, s. 12.
I remember, upon asking our famous Harvey, what induced him to think of a circulation of the blood, he said, that observing the valves in the veins of many parts of the body, so placed as to give a free passage to the blood towards the heart, but to oppose the passage of the venal blood the contrary way, he imagined that so provident a cause as nature had not thus placed so many valves without design; and as no design seemed more probable than that the blood could not well, because of the interposing valves, be sent by the veins to the limbs, it should be sent through the arteries and return through the veins when valves did not oppose its course that way.
Boyle On the Final Causes of Natural Things. On the Proposition: ’Tis often allowable for a naturalist, from the manifest and apposite uses of the parts of animal bodies, to collect some of the particular ends for which the Creator designed them: and in some cases we may, from the known nature and structure of the parts, draw particular conjectures about the particular offices of them.