TRANSLATOR'S INTRODUCTION. v 



treats of the diseases of the brain and nervous system. In 

 these, as well as in his other neurological works, Willis follows 

 the line of research which his peculiar position, as Sidley 

 Professor of Natural Philosophy at Oxford, would almost 

 necessarily incline him to take. According to Willis, the vital, 

 sensitive, or corporeal soul, performs two principal offices; 

 namely, first, to form the body of the animal and its organs, 

 and then to render it and them apt and fit for all the purposes 

 of the life of the individual. The better to illustrate his views, 

 he devotes a chapter to a description of the various kinds of 

 lower animals, including therein zoology, and comparative 

 anatomy and physiology. To this corporeal soul he ascribes 

 all the emotional, instinctive, and involuntary acts. Touching 

 this class of movements, he observes, (I quote the quaint, 

 vigorous language of Pordage's translation,) — " First, as to 

 what regards natural Instincts, it is a great and most ancient 

 Notion, That there is, in all Living Creatures, an innate Conser- 

 vation of themselves; to wit, that every Individual might 

 preserve itself as long as it can. This is a Law of Divine 

 Providence, inbred in all creatures, which gathers together the 

 Principles of Life like a Bond, otherways apt to be dissipated 

 and to depart one from another, and on which, as the Basis, 

 the Duration or Continuance of the whole World stands.^' 

 " This being supposed, it necessarily follows, that all Animals 

 ordained for this end, are furnished also with certain fit means 

 for following the same, wherefore they ought to know, by 

 Natural Instinct, whatsoever things are Congruous and benign, 

 and what are incongruous or hurtful to them ; and that they 

 should follow these with hatred and aversion, and those vdth 

 Love and delight. Hence it is, that every one of them are able 

 to choose Food proper for themselves, and to seek it, being 

 absent, and remote from their eyes ; And, from an implanted 

 disposition of their Nature, are skilful to know and oppose 

 Enemies, to love their Friends, to get a female fit for themselves, 

 and to make ready whatever may conduce to the Procreating 

 and Cherishing their young; besides many other Kinds of 

 powers and habits, granted to us not without Learning and 

 Study, are originally fixed on the prcecordia of the Beast.'' ^ 



' *' Quod autern spectat ad imtinctus naturales, antiquissima, et maxime generalis 

 notio, cunctis animalibus innata est sui ipsius conservatio, nempe ut unumquodque 



