  Part of the reason for this “activist” conception of Soul on Ficino’s part had to do with a search to find forces binding human beings to one another. For Ficino, love linked all things together; and love flowed first from God into all existing things, which consequently shared the property of similarity, outwardly different as they might be on the surface. It is for this reason that “spirit,” or spiritus, was so important in Ficino’s thought. Ficino suggests: “Spirit is defined by doctors as a vapor of blood – pure, subtle, hot, and clear. After being generated by the heat of the heart out of the more subtle blood, it flies to the brain; and there the soul uses it continually for the exercise of the interior as well as the exterior senses” (Ficino in Kaske and Clark 1988, 1.2, 11–15, p. 110). This blurring, to modern eyes, of the metaphysical and the physical, in which the “immaterial” soul can use a vaporous material entity to have effects on the physical world, presents Ficino at his most characteristic. Love between people occurs when the lover’s spirit is exhaled toward the beloved and the beloved returns the gesture reciprocally; unreciprocated love can thus become a kind of homicide, as one human being loses a vital element to another. “When we speak about Love,” Ficino writes (and here he means earthly love), “you should understand this as meaning the desire for beauty. For this is the definition of love among all philosophers.” Ficino goes on: “The purpose of love is the enjoyment of beauty” (Ficino 1576, 1322–23; Kristeller 1988, 282).