SCIENCE AN OUTGEOWTII OF COMMON KNOWLEDGE. 123 



tity ; and once more prove the difference to be one of de 

 gree only. For, on the one hand, the commonest positive 

 knowledge is to some extent quantitative ; seeing that the 

 amount of the foreseen result is known within certain wide 

 limits. And, on the other hand, the highest quantitative 

 prevision does not reach the exact truth, but only a very 

 near approximation to it. &quot;Without clocks the savage 

 knows that the day is longer in the summer than in the 

 winter ; without scales he knows that stone is heavier than 

 flesh : that is, he can foresee respecting certain results that 

 their amounts will exceed these, and be less than those he 

 knows about what they will be. And, with his most deli 

 cate instruments and most elaborate calculations, all that 

 the man of science can do, is to reduce the difference be 

 tween the foreseen and the actual results to an unimportant 

 quantity. 



Moreover, it must be borne in mind not only that all 

 the sciences are qualitative in their first stages, not only 

 that some of them, as Chemistry, have but recently reached 

 the quantitative stage but that the most advanced sciences 

 have attained to their present power of determining quan 

 tities not present to the senses, or not directly measurable, 

 by a slow process of improvement extending through thou 

 sands of years. So that science and the knowledge of the 

 uncultured are alike in the nature of their previsions, widely 

 as they differ in range ; they possess a common imperfec 

 tion, though this is immensely greater in the last than in 

 the first ; and the transition from the one to the other has 

 been through a series of steps by which the imperfection 

 has been rendered continually less, and the range continu 

 ally wider. 



These facts, that science and the positive knowledge of 

 ll.e uncultured cannot be separated in nature, and that the 

 one is but a perfected and extended form of the other, 

 must necessarily underlie the whole theory of science, its 



