International Journal of Preventive Medicine (Int J Prev Med)2008-78021172020090920087802ENTraditional and Complementary Medicine Research Center, Arak University of Medical University, ArakTraditional and Complementary Medicine Research Center, Arak University of Medical University, Arak20200825Dear Editor, An investigation of the effects of studies on the effect of seasons and weather on the incidence of stroke indicates a contradiction in their findings.[1] Since the effect of the seasons on stroke has been recognized for centuries, and great physicians such as Rhazes (865-925 AD) and Avicenna (980-1037 AD) have elaborated on this effect and its contributing factors. The purpose of the present study is to investigate the views of the scholars of the Persian Medicine in this regard. The sages of this doctrine believe that bodily health depends on the balance between the four humours and their unique temperament, viz.: (i) Dam (blood) as ‘hot and moist’, (ii) Safra (yellow bile) as ‘hot and dry’, (iii) Balgham (phlegm) as ‘cold and moist’, and (iv) Sauda (black bile) as ‘cold and dry’.http://ijpm.mui.ac.ir/index.php/ijpm/article/view/2287http://ijpm.mui.ac.ir/index.php/ijpm/article/download/2287/717718129