SEVENTEENTH AND EIGHTEENTH CENTURIES 1x5 



particular act of creation; life, says he, is not a metaphysical characteristic 

 of living creatures, but a physical quality of matter. 



Since, then, the most vital quality of life is the power of reproduction, 

 Buffon devotes very close study to it. For this purpose he does not start from 

 the most highly organized creatures, but begins his investigation — this, 

 too, a modern feature — with the most primitive form of reproduction — 

 that by means of division in plants and primitive animals. Why is it that a 

 severed branch of a twig of a tree grows up into a new tree, that a piece of 

 polypus gives rise to a new polypus? Buffon answers this question by assum- 

 ing that the plant and the animal are composed of a mass of particles formed 

 like the individual in its entirety, and which therefore, when they become 

 detached, can develop further and form a new individual of the same kind. 

 This theory of independent particles, the idea for which he undoubtedly got 

 from Leibniz's monad theory, Buffon further develops to form the basis of 

 his conception of all the phenomena and functions of life; just as inanimate 

 matter is composed of an incalculable mass of minute particles, so there 

 exists in nature a vast number of organic particles that are animate and 

 formed like animate beings. ' 'Just as there may be required perhaps a million 

 minute salt cubes to form one grain of sea-salt, so it would take millions of 

 organic particles similar to the whole to form a bud containing the individual 

 of a tree or a polypus." By making this assumption Buffon also seeks to get 

 rid of the preformation theory, which was generally embraced by his con- 

 temporaries and which he keenly criticizes, maintaining among other things 

 that it would presuppose an infinite number of daughter individuals con- 

 tained in the original mother animal, which in itself is an entirely irrational 

 supposition. But when it comes to setting up an acceptable theory of sexual 

 reproduction in place of the preformation theory, Buffon comes to realize, 

 as he himself openly acknowledges, that it is easier to destroy than to build 

 up. He founded a general physiological hypothesis according to which 

 animals through the food absorb a quantity of these ubiquitous organic 

 particles and in the various organs of the body assimilate from these what the 

 body requires; whatever is left is collected in the genital organs and gives 

 rise to individuals like the parents. That the embryo is thus formed by a 

 combination of a mass of minute independently living particles he believes 

 to be proved by the spermatozoa existing in the seminal fluid; that the female 

 sexual product actually consists of similar minute beings he also believes he 

 had proved by a microscopical study of the ripe follicles in the mammalian 

 ovary; in their fluid he believed that he had found mobile life-elements 

 similar to those in the semen which he actually illustrates^ and which in his 



^ What Buffon and his collaborators — he quotes several, including the English micro- 

 scopist Needham — actually saw in the follicular fluid it is difficult to say; perhaps detached 

 cells from the follicular epithelium; maybe also coagulation products. 



