ADVANCEMENT OF LEARNING 181 



tion the immortality, or derogate from the sovereignty of 

 the soul, let him find an answer in the instances, either of 

 an infant in its mother s womb, which shares in the vicis 

 situdes, and yet is distinct from its mother s body, or of 

 monarchs, who, though in possession of absolute power, 

 are frequently influenced and swayed by their servants. 



The other part, which considers the operations of the 

 soul upon the body, has likewise been received into medi 

 cine; for every prudent physician regards the accidents of 

 the mind as a principal thing in his cures, that greatly 

 promote or hinder the effects of all other remedies. But 

 one particular has been hitherto slightly touched, or not 

 well examined, as its usefulness and abstruse nature re 

 quire; viz., how far a fixed and riveted imagination may 

 alter the body of the imaginant; for though this has a 

 manifest power to hurt, it does not follow, it has the same 

 to relieve: no more than because an air may be so pestilent 

 as suddenly to destroy, another air should be so wholesome 

 as suddenly to recover. This would be an inquiry of noble 

 use; but, as Socrates would say, it requires a Delian diver, 

 for it is deep plunged. 18 



But among these doctrines of union, or consent of soul 

 and body, there is none more necessary than an inquiry into 

 the proper seat and habitation of each faculty of the soul in 

 the body and its organs. Some, indeed, have prosecuted 

 this subject; but all usually delivered upon it is either con 

 troverted or slightly examined, so as to require more pains 

 and accuracy. The opinion of Plato, which seats the un 

 derstanding in the brain, courage in the heart, and sensu 

 ality in the liver, should neither be totally rejected nor 

 fondly received. 14 



13 Laertius Life. 



14 Plato s Timseus, and Aristotle on the Generation of Animals. 



