Dear Editor-in-Chief: According to the literature available on Iranian traditional medicine (ITM), elements (fire, air, water, soil) are small bodies indivisible to different components and are essential constituents of human and non-human beings. Warmness, coldness, wetness and dryness are the basic qualities that each of the elements has a pair of them: fire is warm and dry, air is warm and wet, water is cold and wet, and soil is cold and dry. After action and reaction of these four elements, a homologous quality/qualities will be dominant in composite objects which is called temperament…