A TREATISE 



t motion about our heart. To which purpofe we arc to remem- 

 ber, that this motion is performed in the moft fubtile and thin 

 fubftance, that can be imagined: they are the vitall fpirits, that 

 do all this work $ which are fofubtile,fo agile, andfo hot, that 

 they may in feme fort be termed fire. Now ifwe reflect how 

 violent fire is, we need not wonder at the fnddaine and great 

 motion ofthelepaffions. 



But we mult further take notice, that they are not in the- 

 greateft cxcefTe , but where the living creature hath been long- 

 inured and exerci/ed unto them,either directly or indireiMy : io 

 that they arrive not to that pitch fo much out of the power of the 

 agendas out of the preparation and difpofition of the patient j as 

 when cold water hath been often heated by extinguishing red 

 hot irons in it, after fome repetitions a few quenchings 

 will reduce it from cold to boyling,that at the firft would fcarce 

 have made it Jukewarme : and accordingly we fee a heart , that 

 for a long time hath loved,, and vehemently hath defired enjoy - 

 ing, is tranfported in a high degree, attheleaft fight and re- 

 nuance of flrcaks from its beloved object 5 and is as much de-, 

 jefted, upon any the leaft deprivation of it : for to fuch an ob- 

 jcc^the living creature is hurried away by a force much refem- 

 bling the gravity or celerity of a denfe body, that is fet on run- 

 ning down a iteepe hill ; unto which, the onely taking away of a 

 weake let or thelcaft ftop.giveth a precipitate courfe,not out of 

 the force of what is done to it, but out of the force which was. 

 formerly in the thing, though for theprefent it lav there un- 

 difcovered : and fo likewi/e in thefe cafes, the objeft rather 

 giveththeoccafionof the violent motion, then the force or 

 power to it. 



Thefe things being thus determined, fome perad venture may 

 aske, how it commeth topafie, that the fpirits whkh caufemc- 

 tion,being fent on their arrant by the brain e, do alwaycs hit the 

 right way, and light duly into thofe very finewes, which move 

 th^ living creature according as is requifite for its nature ? 

 Since all thepaflages are ope^what is it that governerfa them/o 

 as they never mifiake , and the animall is never driven towards 

 harme in fteedofflying from it? Who is their guide in thefe ob- 

 /cure paths ? But it were to impute ignorance to themaker, to 

 Think that he framed all the pajlages alike , and fo every one of 



them : 



