The Canon of Medicine

Fifth Erratum of Avicenna concerning napellus.

Is it not for this reason that Avicenna writes in the second book of the Canon, if there are indeed any fools and dull-witted people who wish to believe him in all things, that napellus monkshood/aconite is a pernicious poison, and yet he urges it to be drunk, when he afterwards adds: "It deletes albaras leprosy/vitiligo, both applied as an ointment and drunk." The poison which is called napellus by herbalists in our age is called aconitum by the Greeks and Latins, about which Virgil writes: "The stepmother mixes the aconites." Thus it now appears that Avicenna imitates not so much a tyrant as the customs of a stepmother.

Sixth Erratum of Avicenna on the root of pentaphyllum.

The root of pentaphyllum cinquefoil, commended by Dioscorides, is written by Avicenna in the second book of the Canon to be a pernicious medicine, to such an extent that Savonarola, a physician famous in our time, does not dare to give it in quartan fever for no other reason than that it is condemned by Avicenna. He has such authority among the physicians of our time, and especially among our Papians and Montpelliers, that he makes a deadly medicine salutary, just like pedem comunum, and makes a salutary one pernicious, like the root of pentaphyllum or its juice. For Jacob of Fodi, nicknamed the Aggregator, numbers the juice of this root among pernicious poisons on the authority of Avicenna. Perhaps, however, as far as the root of the crow's foot is concerned, it is not so much Avicenna as the physicians themselves, who do not correctly understand Avicenna, who are to be reprimanded.

On Cassia Fistula. Seventh Erratum.

Younger physicians use cassia fistula and manna for softening the bowels. The Greeks, however (I speak of the ancients), made mention of neither, either because they did not know them or perhaps they did not approve of them in the practice of medicine. Indeed, Galen entirely disapproves of a fruit similar to cassia fistula, which is called ceratia by the Greeks and, by a corrupted term (as I think), carnubium by the Arabs, to such an extent that in his second book On Foods, he wishes—or thinks it would be better—that it would never be brought to the people of his own race from the places in which it is born. Occasioned by these words, I am moved to wonder how Avicenna, who confesses himself to be an interpreter of Galen, nonetheless incorrectly cites him as saying that this fruit is not brought to other regions. For Galen would have wished in vain that it not be brought to his own people if it were not brought to other regions from the soil in which it is born. I said that ceratia is a fruit similar to cassia fistula, because the color of the bark is the same, and the pulp is also sweet, just like cassia fistula, and furthermore, this same pulp is distinguished by similar seeds, as not only the senses but also the authority of Serapion proves, who, in the chapter on cassia fistula, says that inside the reeds of the cassia are lamellae thin plates/layers of black flesh, and there are walls dividing between them, and between lamella and lamella are grains, like the grains of xilocaracta and of the same magnitude, whose color is between glaucous and red. By xilocaracta, as Leonicenus asserts, we ought to understand the fruit that the Greeks call both ceratia and xilocaracta, and the Latins call siliqua dulcis carob. The Arabs, however, call it carnubium. But the siliqua dulcis is the same thing, which is also a property of cassia fistula. For the pulp of both, when fresh, loosens the bowels; when dried, however, it rather constricts them. This is also testified by Galen, Paul, and Pliny regarding the siliqua dulcis. Concerning cassia fistula, however, it is established by the experience of physicians. Yet, one must remind younger physicians here that one reads of cassia fistula in the books of the Greeks, but not the one you are inquiring about, which has the power of softening the bowels and is therefore called siliqua pharmaceutica pharmaceutical carob by some moderns, but rather a certain species of cassia lignea cinnamon-like bark which is called fistula by those same Greeks. Wherefore, one must be more diligent so that when we find "cassia fistula" written in the books of the Greeks, we do not think the other is meant, of which the Arab authors speak, which they use in Arabic medicine to induce menstruation, since they ought to use cassia lignea for that same purpose according to the authority of Galen and other physicians. For the Greeks appear to have neglected this other cassia fistula, just as [they neglected] other fruits of trees which the Arab authors and younger physicians, following them, have in such frequent use that they have completely looked down upon the former.

On Manna. Eighth Erratum.

Regarding the opinion of Manna in Dioscorides.

Oh, if only I could prove the opinion of Simon of Genoa, who in the letter M, in the chapter on honey, says that the ancient Greeks did not have knowledge of saccharum sugar which we use in various compositions. And he will say that which he insinuates in his words at the cited passage: that manna in Dioscorides is the saccharum named by the same Dioscorides in the chapter on honey. But with Leonicenus, I think otherwise: that saccharum in him, just as in Galen, is that which we commonly call zucharo sugar, which the ancient Greeks said was a species of honey. But they spoke only generally of manna, not specifically, even though Mesue falsely cites Galen in three places speaking of manna: in the chapter on manna, the chapter on scammonea, and the chapter on the confection of manna according to the discovery of Galen. For manna among the Greek authors is not a medicine that softens the bowels but is rather an abstergent, and more frequently manna thuris frankincense manna, which is called manna simply. For (as Galen says in book 13 of the Curative Art), that which is called manna is a shaking/exudation of incense, which participates in a certain small astringent power, and for that reason, it is better for certain things than incense itself. For this, specifically, has only that which is to be suppurated, and is the least astringent, and especially that which is fat and whiter in color; just as that which is more yellow dries more. Those, however, which are called manna admit a little bit from the bark of the incense, from which it has its astringent power. I have said elsewhere what manna thuris is in Dioscorides; but the Greek authors compare the medicine of manna to cassia fistula, and if not specifically, at least generally they write, since this manna, which loosens the bowels, can be referred to the chapter on honey. Just as it is also placed by Galen: for these are the words of Dioscorides on saccharum herb; it also calls a certain saccharum a species of honey existing in India, which solidifies and is found in Arabia Felix in reeds, similar in substance to salt, and breaks under the teeth like salt, although it is called zucharo by us. But he may have thought it to be a species of manna, so that by this one reason alone Mesue could be excused for citing Galen writing about manna. If by manna, he understands saccharum which Dioscorides and Galen judge to be a species of honey. For manna, of which the Arab authors speak more specifically, differs clearly from sugar and honey, yet it is clearly [different] by the authority of Avicenna and Serapion, for one is tereniabin, which is a species of manna...