1.1 BIOLOGY, PHYSICS AND CHEMISTRY 31 



natural systems which we call living beings must be as- 

 similated to the artificial systems that science cuts out 

 within inert matter, or whether they must not rather be 

 compared to that natural system which is the whole of 

 the universe. That life is a kind of mechanism I cordially 

 agree. But is it the mechanism of parts artificially isolated 

 within the whole of the universe, or is it the mechanism 

 of the real whole? The real whole might well be, we con- 

 ceive, an indivisible continuity. The systems we cut out 

 within it would, properly speaking, not then be parts at 

 all; they would be partial views of the whole. And, with 

 these partial views put end to end, you will not make 

 even a beginning of the reconstruction of the whole, any 

 more than, by multiplying photographs of an object in 

 a thousand different aspects, you will reproduce the object 

 itself. So of life and of the physico-chemical phenomena 

 to which you endeavor to reduce it. Analysis will un- 

 doubtedly resolve the process of organic creation into an 

 ever-growing number of physico-chemical phenomena, 

 and chemists and physicists will have to do, of course, 

 with nothing but these. But it does not follow that 

 chemistry and physics will ever give us the key to life. 



A very small element of a curve is very near being a 

 straight line. And the smaller it is, the nearer. In 

 the limit, it may be termed a part of the curve or a part 

 of the straight line, as you please, for in each of its points 

 a curve coincides with its tangent. So likewise "vitality" 

 is tangent, at any and every point, to physical and chemical 

 forces; but such points are, as a fact, only views taken 

 by a mind which imagines stops at various moments 

 of the movement that generates the curve. In reality, 

 life is no more made of physico-chemical elements than a 

 curve is composed of straight lines. 



In a general way, the most radical progress a science 



