As we have spoken of blood-letting, note that it is most proper and avails most for persons of robust and stout habit, and from whom but little is dissipated. Not thus for the folk who have thin bodies and dominance of choler in the pit of the stomach, as for them it avails not. In cold wet weather it avails most, and for dark folk who are wont to consume much meat.65 It may be asked hereif there be little good blood in the body, and many crude humours, does a vein avail in that case? It is proven according to Galen that it does avail, and Hippocrates says, regarding the people that fill themselves excessively and are drunken (?), who cannot but have crude humours, and where there is little good blood and a plethora of raw humours, blood-letting is beneficial.