The History of Things 71 



pose that the sum-total of matter and energy in 

 the whole system of things suffers any loss or 

 makes any gain. If apparently new properties 

 arise, we believe that they are old properties in 

 new guise. We can make apparently very new 

 things ourselves, such as dynamite, but we know 

 that the properties of dynamite can be resolved 

 into the properties of simpler things. Even when 

 we discover a new thing like Radium, with alto- 

 gether unexpected properties, we soon follow it up 

 by discovering radio-activity in many other cases. 

 It may be, for all we know, an intrinsic property of 

 matter to emit rays. In any case, we revise our 

 conception of what is "given," and say that there 

 is nothing new under the sun. In short, in the 

 history of the earth, we believe we have to do with 

 a continuous natural development, in which ante- 

 cedents pass over into their consequents, and we 

 feel no need for any cause in the strict sense ex- 

 cept the first cause which is taken for granted 

 throughout. 



Later on, we shall try to show that this way of 

 looking at things must be somewhat enlarged 

 when we come to the emergence of living organisms 

 upon the earth, when we have to do with autono- 

 mous agents, when we study intelligent behaviour, 

 when we face the biggest fact in all science man, 

 with his ideas and ideals a thinking reed, who, 

 if the universe should crush him, would still be 



