220 LETTERS TO BROTHER JOHN. 



absolutely necessary to the existence of man. She 

 might hav constructed him so as to live without 

 air; but then some other contrivance must have 

 been adopted ; and to have instituted a contrivance 

 which did not exist, in order to effect a purpose 

 that might be well effected by a contrivance 

 already existing (viz. air), would have been to 

 waste her means, and unnecessarily exhaust her 

 energies ; which she never does. And as air, which 

 is one of the component parts of the system of the 

 world, is absolutely necessary to the existence of 

 man, so the other so-called " discomforts " of life, 

 such as, cold, wet, hard fare, hard lodging, which are 

 also component parts of the system of the world, 

 are absolutely necessary to the perfection of his 

 HEALTHY existence. 



As in the case of air ; so, in the case of other dis- 

 comforts of life, Nature, it is true, could have 

 fulfilled her task without them : she might have 

 contrived other means to preserve the health of the 

 human machine : but these were ready-made to her 

 hand; and she made use of them at once, as she 

 always does, rather than waste her energies by the 

 invention of new ones. 



Thus are all the systems of things, animate and 

 inanimate, dovetailed into each other. One sup- 



