134 THE LIFE OF SCIENCE 



yet see the latest developments of science in their true perspective. 

 Of course, we believe we can ; we think in good faith that we can 

 single out the most pregnant discoveries of our own days, but 

 the whole of past history is there to testify that contemporary 

 judgments are always precarious. This is natural enough. The 

 value of a theory, the importance of a fact, depend entirely on 

 the conclusions which may be derived from them, on the fruits 

 they will bear, and scientists are not prophets. Comte's saying, 

 "Savoir arm de prevoir," is often misquoted. It is true the sci- 

 entist is able to foresee and to anticipate the immediate conse- 

 quences of certain events, and therein lies the secret of his material 

 power. But he is not able to predict the future except within the 

 very narrow sector controlled by his knowledge and even there 

 he is hedged in with all kinds of restrictions. Indeed no man is 

 more chary of predictions than the true scientist. 



There are two main reasons for studying the history of science : 

 a purely historical one, to analyze the development of civilization, 

 i.e., to understand man, and a philosophical one, to understand 

 the deeper meaning of science. Now from either point of view, 

 the history of ancient and medieval science is at least as useful as 

 that of modern science. He who knows only one of these histories 

 does not really know the history of science, nor does he know the 

 history of civilization. 



I shall try to make this more concrete by dealing at greater 

 length with the earlier parts of our history. If it were not so futile 

 to pick out a single period as the best — for each period was the 

 best from a certain point of view and each was an indispensable 

 link in the chain of ages — I would say in opposition to the un- 

 critical scientist that the most important was, not the latest, but 

 the earliest. Nothing is more difficult than to begin. And what can 

 be more fundamental than a good beginning? Is it not the founda- 

 tion upon which all the rest will be built? 



Unfortunately we shall never have any adequate information on 

 this, the most critical period of man's history, when he was grati- 



