458 THE PRINCIPLES OF SCIENCE. 



We may lay down the general form of the equations, ex- 

 pressing the demand and supply for two or three commo- 

 dities among two or three trading bodies, but all the 

 functions involved are of so complicated a character that 

 there is not much fear of scientific method making a 

 rapid progress in this direction. If such be the prospects 

 of a comparatively formal science, like Political Economy, 

 what shall we say of Moral Science \ Any complete 

 theory of morals must deal with quantities of pleasure 

 and pain, as Bentham pointed out, and must sum up the 

 general tendency of each kind of action upon the good 

 of the community. If we are to apply scientific method 

 to morals, we must have a calculus of moral effects, a 

 kind of physical astronomy investigating the mutual per- 

 turbations of individuals. But as astronomers have not 

 yet fully solved the problem of three gravitating bodies, 

 when shall we have a solution of the problem of three 

 moral bodies ? 



Now the sciences of political economy and morality are, 

 comparatively, abstract and general, treating mankind 

 from simple points of view, and attempting to detect 

 general grounds of action. They are to social phenomena 

 what the general sciences of chemistry, heat, and electri- 

 city, are to the concrete science of meteorology. Before 

 we can investigate the actions of any aggregate of men, 

 we must have fairly mastered all the more abstract 

 sciences applying to them, somewhat in the way that 

 we have acquired a fair comprehension of the simpler 

 truths of chemistry and physics. But all our physical 

 sciences do not enable us to predict the weather two days 

 hence with any great probability, and the general problem 

 of meteorology is almost unattempted as yet. What shall 

 we say then of the general problem of social science, which 

 shall enable us to predict the course of events in a nation I 



There have indeed been several writers who have pro- 



