LETTERS TO BROTHER JOHN. 97 



us to decide upon the qualities of whatever matters 

 are presented to us for food. But the medium, 

 through which these organs are enabled to render 

 us these important offices, is their SENSIBILITY. 

 For if the eye were insensible to light, we could not 

 see the ear to sound, we could not hear the nose 

 to odours, we could not smell the tongue to fla- 

 vours, we could not taste the skin to touch, we 

 could not feel. In literal fact, then, you see it is 

 SENSIBILITY, after all, which establishes this neces- 

 sary relation, of which I have spoken, between our- 

 selves and surrounding objects ; the organs being 

 no more than the instruments by which SENSIBILITY 

 exerts its influence. SENSIBILITY, then, is our 

 guardian angel ; it is, like the sailor's " sweet little 

 cherub," an invisible agent, that for ever watches 

 over " our lives and safeties all." 



Every organ has a kind of peculiar sensibility 

 of its own. Thus, the sensibility of the eye is not 

 aifected by the stimulus of sound ; nor can the 

 sensibility of the ear take cognisance of the 

 stimulus of light. The nose is insensible to the 

 stimulus of flavours, and the tongue knows nothing 

 of odours. From this it follows, that the sensi- 

 bility of each organ is adapted to be properly 

 affected by certain stimuli only. All others than 



