30 THE BIOLOGICAL PROBLEM 



It is easy to discover the source of the fundamental error 

 which led to hasty conclusions. The magnificent conquests 

 of science induced us to believe that, by increasing indefinitely 

 the precision of our measurements, we would be able to 

 predict phenomena with ever-increasing accuracy. Unfortu- 

 nately, experimental facts have proved that this hope was, and 

 will always be, vain. It was found that the most capricious 

 irregularities are observed when the precision of the measure- 

 ment exceeds a certain point and enables one to penetrate 

 into the realm of the up till now inaccessible small elements, 

 the postive and negative electron, the photon. No refinement 

 of techniques can enable us to predict the movements of these 

 corpuscles which seem to be determined by the most disordered 

 fantasy. We must repeat that, from a practical point of view, 

 this state of things not only in no way disturbs the evolution 

 of inorganic phenomena nor what we call the principle of 

 causality, but also that this disorder is the necessary condition 

 of our physical laws. These are only rigorous on condition 

 that the movements of the elementary particles are absolutely 

 disorderly, and if they ceased to be so, the laws would cease 

 to be vahd. For, as we said above, the laws of great numbers, 

 of probability, enter into play. All our phenomena are but 

 'envelope' phenomena, and the result, at our scale, of an 

 immense number of elementary phenomena which escape 

 observation. They are statistical laws. There is therefore 

 only one thing changed: our old notion of determinism, our 

 ideas on the real significance of the relation of cause to effect. 

 But the possible occurrence, under certain conditions, of 

 fluctuations which occasionally transpose the 'fantasy' of the 

 elementary corpuscles to a higher scale, still not directly 

 observable, but capable of influencing vital phenomena, 

 Hmits in a certain measure our power of prediction, that is 

 to say our science.^ 



' The development of these concepts would exceed the scope of 

 this book. Nevertheless we think we ought to insist on the fact that 

 these limitations only concern the individual elementary particles and 

 not the current objects of our science. These, as well as ail the 

 phenomena which we study, consist of, or bring into play, such a 



