DescriptionDescartes-reflex.JPG	English: Illustration of the pain pathway in René Descartes' Traite de l'homme (Treatise of Man) 1664. The long fiber running from the foot to the cavity in the head is pulled by the heat and releases a fluid that makes the muscles contract.
Date	1664
Source	Copied from a 345 year old book, Traite de l'homme
Author	René Descartes  (1596–1650)       Alternative names René Des Cartes, Renatus Des Cartes, Renatus Cartesius Description French philosopher and writer Date of birth/death 31 March 1596  11 February 1650  Location of birth/death Descartes  Stockholm  Work location La Flèche; Poitiers; Stockholm  Authority file : Q9191 VIAF: 41838958 ISNI: 0000000121296144 ULAN: 500223252 LCCN: n79061201 NLA: 35035074 WorldCat creator QS:P170,Q9191
Other versions	http://upload.wikimedia.org/wikipedia/commons/0/02/230px-pineal.jpg

"For example, if the fire A is close to the foot B, the small particles of fire, which as you know move very swiftly, are able to move as well the part of the skin which they touch on the foot. In this way, by pulling at the little thread cc, which you see attached there, they at the same instant open e, which is the entry for the pore d, which is where this small thread terminates; just as, by pulling one end of a cord, you ring a bell which hangs at the other end.... Now when the entry of the pore, or the little tube, de, has thus been opened, the animal spirits flow into it from the cavity F, and through it they are carried partly into the muscles which serve to pull the foot back from the fire, partly into those which serve to turn the eyes and the head to look at it, and partly into those which serve to move the hands forward and to turn the whole body for its defense" Descartes, On Man, 1662

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