2 BIOLOGICAL TIME 



is death, the destruction of tissues. Or we would say with 

 Buffon: Life is a minotaur; it devours the organism. If on 

 the contrary we wished to insist on this second phase of the 

 problem of nutrition, that hfe maintains itself only by a 

 constant regeneration of the tissues, we would consider life as 

 a creation accomplished by means of a plastic and regenerating 

 act opposed to the vital manifestations.' 



Claude Bernard was not the man to be enslaved by a formula, 

 as is proved by his words: 'Facts are always more beautiful 

 than the most beautiful theory.' His keen intelligence dictated 

 the lines which even to-day contain the clearest and truest 

 thoughts on the subject. In the course of this introduction 

 we will only express his ideas, and in spite of the rich harvest 

 of new facts of which he had no knowledge, it will be seen 

 that his admirable common sense, his respect of truth, and 

 his genius still dominate all physiology. 



The following pages are extracted from two little-knov/n 

 articles pubhshed in the Revue des Deux Mondes in 1867 and 

 1875. Their perusal will show why they were chosen as an 

 introduction to this book. 



*At the beginning of the nineteenth century, a physiologist 

 could still publish a volume of experiments On the Principle 

 of Life and the Seat of this Principle. We no longer search 

 for the seat of life. We know that it is everywhere, in all 

 the molecules of organized matter. The vital properties 

 are in the living cells. Everything else is but organization 

 and mechanism. The manifold manifestations of life are 

 the expression of thousands and thousands of combinations 

 of elementary organic properties which are themselves fixed 

 and invariable. It is therefore less important to know the 

 immense variety of vital manifestations which nature never 

 seems to be able to exhaust, than to determine rigorously 

 the properties of the tissues from which they spring. That 

 is why to-day all scientific effort is directed towards the 

 histological study of the infinitely small elements which 

 contain the true secret of life. 



