ON THOUGHT IN MEDICINE. 233 



complexity of the nerve-fibres of the brain. But the 

 resemblance to the qualitates occultce of ancient 

 medicine is very suspicious. 



From the entire chain of my argument it fol- 

 lows that what I have said against metaphysics is 

 not intended against philosophy. But metaphysicians 

 have always tried to plume themselves on being philo- 

 sophers, and philosophical amateurs have mostly taken 

 an interest in the high-flying speculations of the meta- 

 physicians, by which they hope in a short time, and 

 at no great trouble, to learn the whole of what is worth 

 knowing. On another occasion * I compared the rela- 

 tionship of metaphysics to philosophy with that of 

 astrology to astronomy. The former had the most 

 exciting interest for the public at large, and especially 

 for the fashionable world, and turned its alleged con- 

 noisseurs into influential persons. Astronomy, on the 

 contrary, although it had become the ideal of scientific 

 research, had to be content with a small number of 

 quietly working disciples. 



In like manner, philosophy, if it gives up meta- 

 physics, still possesses a wide and important field, the 

 knowledge of mental and spiritual processes and their 

 laws. Just as the anatomist, when he has reached the 

 limits of microscopic vision, must try to gain an in- 



1 Preface to the German translation of Tyndall's Scientific 

 > p. xxii. 



