70 THE LIMITATIONS OF SCIENCE 



So far as I can see the hypothetical method has its 

 most illustrious example in Descartes, and instead of 

 aiding us to gain real and clear ideas, he has burdened 

 science with useless and complicated metaphysical sys- 

 tems. Instead of being a symptom of power, the reluc- 

 tance to recognize the limits of science comes rather 

 from a certain intellectual cowardice which refuses to 

 acknowledge the truth, that we cannot attain any knowl- 

 edge of things themselves but only of their attributes 

 as they affect our senses. If we really face the ques- 

 tion; strip our scientific hypotheses of their technical 

 phraseology and complex logic, and try to get a clear 

 and simple idea of what they mean, we find that we 

 have been deceiving ourselves. In the first place, we 

 use words, which ordinarily convey definite ideas, in a 

 sense purely symbolical, and then confuse the image 

 and the reality. For example, when we define space 

 or the ether as a perfect fluid, we deceive ourselves 

 into believing that we have gained a clearer idea of 

 space by applying to it a term which signifies the 

 mobility of matter. But this attribute can be applied 

 only to a material fluid whose change of position may 

 be measured, and such a fluid appeals to us as some- 

 thing essentially different from immaterial space. Nor 

 do we overcome this difficulty by qualifying space as 

 a perfect fluid; any fluid is perfect which satisfies the 

 laws of its nature, and we practice deception when we 

 inject the ethical meaning of perfect, as being some- 



