THE RATIONALE OF PHILOSOPHICAL THOUGHT. 739 



a genuine new departure, while the mathematical method 

 of Descartes and Leibniz degenerated with Christian 

 Wolff into mere external form. 



The only constructive thinker of first importance who 

 was not overawed by the mathematical method, for which 

 he had indeed no real appreciation, was Bishop Berkeley, 

 and it is worth noting that his contribution to philo- 

 sophical thought was not truly appreciated in its 

 originality till late in the nineteenth century. 



Special scientific formulse, such as the Newtonian law 

 of gravitation or the atomistic theory of chemistry, were, 

 in many cases, taken as models — the former by Hume 

 in putting forward the laws of association ; the latter by 

 the British School of Psychology in succession to Hart- 

 ley. Hartley himself had sought to connect these laws 

 with physiological processes in the brain. Kant's earlier 

 works are full of quasi-mathematical reasoning ; but, 

 unlike Newton, he exaggerated the importance of gravi- 

 tation as a fundamental principle, as did Laplace ; and 

 he did not understand the Newtonian laws of Motion 

 which were clearly set out by his contemporary d'Alem- 

 bert in France, 



In the beginning of the century there existed only a e. 



^ ^ '' •' Scientific 



very small number of strictly-defined scientific principles. P['°^^f^^^ 

 The laws of attraction and repulsion and those of atomic of°thr'°° 

 grouping and combination stand out prominently ; to centmy! 

 these were added, about that time, the principle of 

 polarity and that of vital forces — the former through the 

 sciences of magnetism and electricity, the latter through 

 the biological sciences. 



These two conceptions, familiar in earlier times, ac- 



