8 THE GRAMMAR OF SCIENCE 



of several methods by which it may be cultivated. No 

 assertion has been made that the man of science is 

 necessarily a good citizen, or that his judgment upon 

 social or political questions will certainly be of weight. It 

 by no means follows that, because a man has won a name 

 for himself in the field of natural science, his judgments 

 on such problems as Socialism, Home Rule, or Biblical 

 Criticism will necessarily be sound. They will be sound 

 or not according as he has carried his scientific method 

 into these fields. He must properly have classified and 

 appreciated his facts, and have been guided by them, and 

 not by personal feeling or class bias in his judgments. It 

 is the scientific habit of mind as an essential for good 

 citizenship and not the scientist as a sound politician that 

 I wish to emphasise. 



S 3. — TJic First Claim of Modern Science 



I have gone a rather roundabout way to reach my 

 definition of science and scientific method. But it has 

 been of purpose, for in the spirit — and it is a healthy 

 spirit — of our age we are accustomed to question all 

 things and to demand a reason for their existence. The 

 sole reason that can be given for any social institution or 

 form of human activity — I mean not how they came to 

 exist, which is a matter of history, but why we continue 

 to encourage their existence — lies in this : their existence 

 tends to promote the welfare of human society, to increase 

 social happiness, or to strengthen social stability. In the 

 spirit of our age we are bound to question the value of 

 science ; to ask in what way it increases the happiness of 

 mankind or promotes social efficiency. We must justify 

 the existence of modern science, or at least the large and 

 growing demands which it makes upon the national 

 exchequer. Apart from the increased physical comfort, 

 apart from the intellectual enjoyment which modern 

 science provides for the community — points often and 

 loudly insisted upon and to which I shall briefly refer 

 later — there is another and more fundamental justification 



