It would be of no interest to retrace this long history, to remind the reader that Plato placed courage in the breast and the sensual appetites in the abdomen, that the School of Salerno attributed anger to the gall, joy to the spleen, love to the liver. The organic or visceral theory long had an overwhelming preponderance, and Bichat, at the beginning of the century (1800), did not hesitate to write, “The brain is not affected by the passions which have for their _exclusive_ seat the organs of internal life—the liver, lungs, heart, spleen, etc.” From the seventeenth century downwards, the cerebral theory becomes more accentuated; with Gall and Charles Bell the heart is quite dispossessed, and, by way of reaction, the part played by the viscera was almost forgotten. At the present day no one maintains that the heart or any other organ is the seat of an emotion in the sense of feeling it; the consciousness of the affective life only exists through the brain, in which the internal sensations coming from the viscera are represented as external sensations; it is an echo. The brain, says Hunter, knows perfectly well that the body has a liver and a stomach, or, as Carus expressed it, each organ has its _psychische Signatur_. The ideal would be to determine, by means of a complete and well-conducted elementary analysis, the part contributed by each internal organ and function to the constitution of a particular emotion. Nothing of this sort can be attempted: there exist, on this point, only scattered materials and conjectures supported chiefly by the phenomena of morbid states. We shall return to this later on. (See Part II.) Let us at this moment confine our attention to the two predominant organs—the brain, the centre of psychic life; the heart, the centre of vegetative life.