I.  Natural Magic in De vita coelitus comparanda (On Obtaining Life from the Heavens), Book 3 of De vita

1.  Plotinian tripartite scheme of being:  One, Intellect, Soul.  Specifics:  How Soul interacts with the physical world:

2.  Individual souls are fragments of the cosmic self (world soul).  In understanding ourselves, we understand the World Soul.

3.  The seminal reasons are Plotinus' logoi spermatikoi ( Enneads IV, 3, xi).  They exist in the World Soul and reflect the pure, unchanging Ideas in the Intellect.  Through their intermediation, the World Sould creates the forms of physical things, which are dim reflections of the Ideas themselves.  Such physical things include both heavenly bodies (eg, planets and stars) as well as lower, earthly objects.  The forms of heavenly bodies, and the "figures" they enter into (eg, constellations, houses of the zodiac) are more direct reflections of the Ideas and mediate the creation of the lower forms.

4.  Physical things can degenerate and become denatured.  The magician/healer reconstitutes denatured things by remarrying seminal reasons with the products in the physical realm.  This is done via the mediation of the subtle and physically rarified spiritus mundi that is everywhere united to the Soul of the World.

5.  In particular, to reestablish the correspondence between an individual soul and the World Soul, the magician/healer attempts to reestablish links between the patient and heavenly objects (either heavenly bodies or heavenly figures).  This involves setting up systems of arrangements of stones, minerals, herbs, animals, etc., associated with the particular heavenly object that is to be influenced; and recommending the use of associated perfumes and scents and the playing of music evocative of the heavenly object.  All this is augmented by the wearing of a talisman made from material associated with the heavenly object and having inscribed on it a figure which visually depicts the seminal reasons stamped in the heavenly object's nature in one of two ways: the inscribed figure on the talisman may correspond to the form of a heavenly body, or to a heavenly figure.  The talisman acts as a reciever that picks up the spiritus mundi emanating from the World Soul.

6.  This sort of magic is natural and physical, as opposed to supernatural and spiritual.  To see this, let's look at its theoretical basis (a combination of Neoplatonic and Scholastic/Aristotelian concepts).  There are 3 important properties of a talisman that give it its power:
     (a)   The manifest properties of its material;
     (b)   the occult properties of its substantial form; and
     (c)   the occult properties of the figure inscribed on it.
The material of a talisman and its substantial form generate a correspondence between it and a heavenly body (Thomistic doctrine of substantial forms).  This is augmented by the correspondence between the figure inscribed on the talisman and a heavenly figure.  The correspondence thus established can be said to be natural in so far as it depends on naturally occurring substantial forms (Scholastic factor) and, in general on a naturally occuring Neoplatonic hierarchical causal chain.  It is not a correspondence that requires the mediation of an intervening intelligence (like a demon).  Furthermore, in using inscribed figures instead of inscriptions of words, letters or symbols, again, no intermediating intelligence is necessary for deciphering.
 

II.  Ficino on the use of talismans and the distinction between natural and demonic magic

 

If you do not approve of astronomical images, even those that have been found to be good for the health of mortals, remember that I, myself, do not so much approve of them as describe them.  You can, with my permission, or even, if you prefer, with my recommendation, put such things aside.  At least you should not neglect the medicines that have been strengthened with a little planetary help - or you will have neglected life itself.  For I have found, through frequent and long experience, that these medicines, as well as other things made correctly by astrologers, are as different as wine is from water.1

Someone ... will say, “What does a Christian have to do with magic and images?” ... [M]agic and images are not so much recommended by Marsilio but described by him, and he is simply interpreting Plotinus.  Which [his] writings plainly show, if they are read with an open mind ... Nor is Ficino talking about the profane kind of magic which uses the cult of demons ... but the natural kind of magic which seizes, from the heavenly bodies through natural things, benefits for helping one’s health...        In this work the first people of all were the Magi who worshipped Christ at his birth.  Why, therefore, should you be afraid of the name ‘Magus’, as if it were terrifying?  It is a name pleasing to the Gospels, not something wicked and venomous, but signifying a wise man and a priest.  Was not such a Magus the first worshipper of Christ?  If you will permit me to say it, he is like a farmer who cultivates a field, only he is a cultivator of the world.  He does not worship the world, any more than a farmer worships the earth.  But just as a farmer, for the sake of human food, tempers his field to the weather, so this wise man, this priest, for the sake of human health, tempers the lower things of the world to the highest, and like the eggs of a hen, subjects the earthly things to the warmth of the heavens.  This is something that God himself always does, and teaches us to do, and persuades us to do, that the lower things might be generated by the higher, and be moved and ruled.        So, there are two kinds of magic.  One, with a certain ritual, works with demons and often makes predictions.  This is driven out when the Prince of This World is driven out.  The other kind, which subjects natural materials to natural causes, works miraculously.  There are two types of this artifice.  One is curious, the other is necessary.        The former manufactures worthless omens for public display, as when the Persian Magi, using sage that has rotted under excrement while the Sun and Moon take the second aspect of Leo and hold the same grade there, produced something like a blackbird with a serpent’s tail, and then reduced this to ashes, poured them into a brazier, and made a house seem immediately to be full of serpents.  One should run from such silly and even health-endangering stuff.        The necessary kind of artifice should be held onto, however, which joins medicine to astrology.2

III.  Sources for Ficino’s talismanic magic

1.  Yates:  Primarily the god-making passages in the Asclepius and the talismanic recipies in the Picatrix.  Secondarily Neoplatonic sources.

2.  Copenhaver:  Primarily Neoplatonic sources (Plotinus, Proclus, Iamblichus and Synesius) and scholastic sources (Aquinas).  Perhaps Picatrix as well.  The Asclepius is used by Ficino only as a legitimatization device.

Three sources of belief in natural magic present in Ficino:
     (1)   Theoretical - Neoplatonic & Scholastic theories of the cosmos and substantial forms
     (2)   Empirical - Natural histories of occult objects
     (3)   Doxographical - Hermetica

Pingree subnote:  Neoplatonic magic (in particular Proclus) is not talismanic, whereas the magic in the Picatrix is.
 
 

References:

• Yates, F. (1964) Giordano Bruno and the Hermetic Tradition, Univ. Chicago Press, Chapter 4.
• Copenhaver, B. (1990) ‘Natural magic, hermetism, and occultism in early modern science’, in D. Lindberg & R. Westman (eds.) Reappraisals of the Scientific Revolution, Cambridge:  Cambridge Univ Press.
• Copenhaver, B. (1986) ‘Renaissance magic and Neoplatonic philosophy: Ennead 4.3-5 in Ficino’s De vita coelitus comparanda’, in G. Garfagnini (ed.) Marsilio Ficino e il ritorno di Platone, Florence 2:  351-369.
• Pingree, D. (1980) ‘Some of the Sources of the Ghayat al-Hakim’, Journal of the Warburg & Courtauld Institutes 43, 1-15.