LIFE AS MECHANISM 



same bodies from which life has been killed they may 

 be physicists; but they cannot be both. The burden 

 they are trying to put on physics and chemistry is 

 too heavy to be borne. The physicists use the word 

 energy, and they mean just one thing, the combina- 

 tion of matter and motion, and they measure it in 

 foot-pounds; the biologist has violently, and against 

 their protest, seized on the word, energy, and it 

 sounds the same in our ears, but it is not matter in 

 motion, and it is not measured in foot-pounds or in 

 any other physical units; it is not conservative and 

 it cannot be predicted. No biophysicist can examine a 

 horse and tell us when it will move, how fast it will 

 move, or where it will move; but a physicist can an- 

 swer these questions about a hobby-horse containing 

 a clock-work mechanism. And to make matters 

 worse, the vicious use of the word, energy, by the 

 biologists has encouraged the psychologists to go a 

 step further and to use energy as an explanation of 

 thought and emotion ; and in this connection the word 

 loses every particle of its original significance. I have 

 never met the physicist who would admit the least 

 connection between "physical" and ''psychological" 

 energy. It is time physicists should demand that en- 

 ergy be restricted to its established use when it is ap- 

 plied to scientific problems or permit the biologists 

 to have the word and coin another for their own use, 

 just as law-abiding citizens often permit the transfer 

 of their property to the pockets of robbers who use 



C 249 3 



