Full context:   Historically, in the second century AD, the physician Galen described four classical temperaments (melancholic, phlegmatic, sanguine and choleric), corresponding to the four humors or bodily fluids. This historical concept was explored by philosophers, psychologists, psychiatrists and psycho-physiologists from very early times of psychological science, with theories proposed by Immanuel Kant, Hermann Lotze, Ivan Pavlov, Carl Jung, Gerardus Heymans among others. In more recent history, Rudolf Steiner had emphasized the importance of the four classical temperaments in elementary education, the time when he believed the influence of temperament on the personality to be at its strongest. Neither Galen nor Steiner are generally applied to the contemporary study of temperament in the approaches of modern medicine or contemporary psychology.