MODERN BIOLOGY 319 



silence, yet without a knowledge of them it is impossible to gain any idea of 

 Lamarck's scientific development, all the more so as throughout his life he 

 firmly adhered in all essentials to the views he held in his youth. 



In the above-mentioned work, Memoires de physique, Lamarck endeav- 

 oured to form a general theory of existence, a combination of physics, 

 chemistry, and physiology. This theory represents a continuous attack upon 

 what he calls "pneumatic chemistry" — that is, Lavoisier's quantitative 

 method (Part II, ch. xii). For Lavoisier himself Lamarck has nothing but 

 praise, his polemics being invariably objective and honest, but on the com- 

 position of things he has ideas that are entirely his own. Lavoisier had con- 

 ceived combustion as a process of oxidization; Lamarck finds this explanation 

 absurd — the idea of oxygen's being an essential component of both water 

 and air is in his opinion utterly irrational; no chemist has ever seen it and 

 nobody has been able to prove its actual existence. And equally irrational is 

 the theory of chemical affinity as a cause of chemical associations between 

 the elements: "It is not compatible with reason and is therefore impossible." 

 As essential components of nature Lamarck assumes the four known ele- 

 ments — • fire, air, water, and earth — and adds a fifth, light. The purest 

 earth is — rock-crystal. The chemical associations are not at all bound to- 

 gether by any affinity; rather, they strive to disintegrate into their simple 

 components. What creates chemical associations on the earth is exclusively 

 life; all inorganic associations that exist — rocks, minerals, metals — are 

 disintegrated remains of living beings. Lamarck sets up an evolutionary series 

 that is unique of its kind, beginning with blood, bile, urine, bone-substance, 

 snail-shell, and proceeding to increasingly greater "disintegrations" through 

 shell-lime, marble, gypsum, to precious stones, metals, and lastly "simple" 

 rock-crystal. The problem of what life really is is of course a question that 

 largely occupies the mind of Lamarck and is discussed by him with great 

 particularity. The essential factor in life he finds to be motion; an animate 

 being is composed of various parts which affect one another and are kept in 

 motion partly by mutual influence and partly by influence from without, and 

 it undergoes constant change in consequence of this motion. Life itself is 

 motion and nothing else — that is, a purely mechanical phenomenon. The 

 essential components in the living body are partly solid (fibres and mem- 

 branes), partly liquid (blood, lymph, and other special "fluids," of which 

 more later on). Of the functions of life, secretion within the organism is an 

 expression for the afore-mentioned efl"orts made by the chemical associations 

 to disintegrate; nutrition counteracts these eff'orts by providing the living 

 being with fresh substances, a difference being made between the power of a 

 plant to form out of simple alimental substances complex bodies, and the 

 dependence of animals upon these same complex products for their nourish- 

 ment. — In these and other phenomena, in both animate and inanimate 



