Like Ficino and Bruno, Paracelsus believed that magic worked primarily through the imagination, which is not mere illusion or fantasy (phantasia) but a spiritual force that has real effect in the physical world. "Man... is altogether a star. Even as he imagines himself to be, such he is, and he is that also which he imagines. If he imagines fire, there results fire; if war, there ensues war... the imagination is itself a complete sun." Indeed, Paracelsus describes the imagination as a kind of "seminal power," which impresses the "seeds" of the magician's will onto external objects: "God planted the seed in all its reality and specificity deep in the imagination of man.... If a man has the will, the desire arises in his imagination and the desire generates the seed." Imagination is, again, closely tied to sexual desire; thus, a woman can deeply inform the nature of a fetus, bearing children "similar to her imaginations." Conversely, a woman who is overly lustful or unchaste can project dangerous things out of her imaginations, such as incubi, succubi, and even plague. It is through this power of imagination, moreover, that the alchemist makes the physical act of transmuting minerals a spiritual act, through which he himself is transformed, purified, and reborn as a spiritual being: "imaginatio is the active power... of the higher man within.... During this work man is 'raised up in his mind.' ... While the artifex heats the chemical substance in the furnace he himself is morally undergoing the same fiery torment and purification.
This model of alchemy as a spiritual, but also highly "erotic" art and this view of the imagination as a force of active magical power would both have a formative influence on most modern forms of sexual magic.
Hugh Urban, Magia Sexualis