SOURCE: "Albertus Magnus," in A History of Magic and Experimental Science during the First Thirteen Centuries of Our Era, Vol. II, The Macmillan Company, 1929, pp. 517-92.

[In the following excerpt, Thorndike examines Albert's representative thoughts on magic and natural science, his influence on his students, and his reputation among various critics and biographers.]

It may be well at the start to indicate the scope and character of Albert's works in the field of science. In general they follow the plan of the natural philosophy of Aristotle and parallel the titles of the works then attributed, in some cases incorrectly, to Aristotle. We have eight books of physics, psychological treatises such as the De an'ima and De somno et vigilia, both in three books, and works dealing with celestial phenomena, such as the De meteoris and De coelo et mundo in four books each, and with the universe and life in general, such as the De causis et procreatione un'iversi, De causis et proprietatibus elementorum et planetarum, and the De generatione et corruptione. Geography is represented by the De natura locorum, zoology by the twentysix books on animals, botany by the seven books on vegetables and plants, and mineralogy by the five books on minerals. Björnbo called attention to a work on mirrors or catoptric ascribed to "Albert the Preacher" in several manuscripts but which is not included in the editions of Albert's works and which has never been printed. I do not know if this is the same treatise as a treatise on Perspective attributed to Albertus Magnus in a manuscript which Björnbo did not mention. A work on the planting of trees and preserving of wine is sometimes ascribed to Albert in the manuscripts, but is probably rather by Petrus de Crescentiis or Galfridus de Vino Salvo. I think that I have encountered only once in the manuscripts the attribution to Albert of an epitome of the Almagest of Ptolemy and of a Summa astrologiae. Fairly frequently one meets with some brief compendium of all natural philosophy ascribed to Albert, of which perhaps the most common is the Philosophia pauperum or "Introduction to the books of Aristotle on physics, sky and universe, generation and corruption, meteorology, and the soul." These are either spurious, or, if based on Albert's writings, add nothing of importance to them.

Finally we may note a group of works lying on the border of natural and occult science and which have been regarded as spurious: treatises on alchemy and chiromancy, the Speculum astronomiae, the De secretis mulierum, the Liber aggregations, and the De mirabilibus mundi. …

The order in which Albert's numerous works were written is a matter difficult to determine but of some interest, although not of very great importance, for our investigation. The statement of Peter of Prussia that the translation of Aristotle "which we now use in the schools" was made by Thomas of Cantimpré at the suggestion of Aquinas, "for in Albert's time all commonly used the old translation," would, if true, suggest that Albert wrote his Aristotelian treatises early in life, since he actually outlived Aquinas. But not much reliance is to be placed in this statement of Peter, since it is reasonably certain that Thomas of Cantimpré at least did not translate Aristotle. I have been impressed by differing and almost inconsistent attitudes in different treatises by Albert, for instance in his attitude towards magic, which seem to hint that his opinions changed with the years, although it may be attributable, as in some other authors, to the fact that in different works he reflects the attitude of different authorities, or approaches different subjects with a different view-point, writing of theology as a theologian, but of Aristotle as a philosopher. However, [Clemens Baeumker, in Die Stellung des Alfred von Sareshel, and Arthor Schneider, in Die Psychologie Alberts des Grossen, 1906], pursuing in connection with Albert's writings a different line of investigation from mine, have been struck with the same thing and have concluded that Albert underwent a gradual intellectual development. They note that in his Commentaries on the Sentences he is still glued to the Augustinian tradition, while in his Summa he is strongly influenced by Aristotle and working for a synthesis of Aristotle and Augustine. Finally, in his philosophical and scientific works, related to the genuine and spurious works of Aristotle, "he goes very far with this Arabian-trimmed Neo-Platonism, often so far that he finally feels compelled to explain such exposition as mere citation, and in the strife of conflicting masses of thought surging within him refers for his own personal interpretation to his theological writings." From this it would seem that most of Albert's theological treatises were written before his scientific works, based upon Aristotle and spurious Arabic and other additions. But we have seen that many of his Aristotelian treatises were completed before the Speculum naturale of Vincent of Beauvais, whereas his Sentences name 1246 and 1249 as current dates.

But while Albert may sometimes refer to his theological works for his own personal views, he does not do so in those passages which will especially concern us, and it is in his works on natural science that he seems to the modern reader more original. Indeed Jessen declared that repeated perusal of Albert's many writings in the field of natural history had convinced him that he was "original everywhere, even where he seems to copy." Jessen, indeed, held that Albert would have been even more original and outspoken than he is, but for fear of the charge of heresy; but in my opinion there is little to support such a view. Be that as it may, in his works on natural science Albert does not merely repeat past ideas whether of Aristotle or others, but adds chapters of his own drawn in large measure from his own observation, experience, and classification. It is in his scientific works that he is as superior to Aquinas as the latter is generally considered to surpass him in the purely metaphysical and theological field. Since writing the foregoing sentences I have found that Peter of Prussia expressed much the same view in his life of Albert written toward the close of the fifteenth century. Peter says, "Moreover, this should be understood, that after Aristotle faith is to be put in Albert above all who have written in philosophy, because he has himself illuminated the writings of almost all philosophers and has seen wherein they spoke truly or falsely, nay more, since he himself was experienced above all others in natural phenomena. It may be that some, relying on their metaphysics or logic, can impugn him by certain arguments, but I think that no matter of great concern, since Albert himself says that faith is to be put in anyone who is expert in his art."

Albert's scientific fame perhaps reached its zenith shortly before the publication of Darwin's Origin of Species in 1859. In 1836 and 1837 Ernst Meyer published in Linnaea his "Albertus Magnus, ein Beitrag zur Geschichte der Botanik im XIII Jahrhundert," and later in his History of Botany ranked Albert as the greatest botanist during the long period between Aristotle and Theophrastus on the one hand and Andrea Cesalpini on the other. "Yes, more than that. From Aristotle, the creator of scientific botany, until his time this science sank deeper and deeper with time. With him it arose like the Phoenix from its ashes. That, I think, is praise enough, and this crown shall no one snatch away from him." In the meantime, at Paris in 1853, Pouchet had published his History of the Natural Sciences in the Middle Ages with the sub-title, Or Albertus Magnus and his age considered as the point of departure of the experimental school. But the extreme praise of Albert had occurred a little earlier in lectures on the history of science delivered by De Blainville at the Sorbonne in 1839-1841 and published a few years later. De Blainville too centered his discussion of medieval science about Albert, to whom alone he devoted some ninety pages, extolling him for affirming the permanence of species and for "broadening" Aristotle to fit the requirements of theology. In ten theses in which De Blainville undertook to sum up briefly the chief legacies of Albert to science, he held that he completed and terminated the circle of human knowledge, adding to Aristotle the scientific demonstration of the relations of man with God; that he extended the scope of observation to every scientific field except anatomy; that he created the description of natural bodies, a thing unknown to the ancients; and that in filling in the gaps in Aristotle's writings he was the first to embrace all the natural sciences in a complete plan, logical and perfectly followed. "In accepting therefore with the Christian Aristotle," concluded De Blainville, "the first verse of Genesis, 'In the beginning God created heaven and earth,' and the consequences which follow it, we have, in my opinion, reached the apogée of the encyclopedia of human knowledge, which can now only extend itself in respect to the number and the deeper knowledge of material objects."

This passage from De Blainville, who seems to have been a Roman Catholic, is very interesting as showing how the progress of modern science in his own time and the centuries just preceding could be almost completely miscomprehended by a professed historian of science. We must not, however, suppose that such misconceptions of the progress of science were universal or even general in the first half of the nineteenth century. The article on Albertus Magnus in the Histoire Littéraire de la France, which was published in 1838, recognizes that Albert did not extend the bounds of the sciences as much as had been supposed, and that progress had been made since the sixteenth century which rendered that part of his works "almost useless." The passage from De Blainville is interesting also as showing the same intimate connection presupposed between Christian theology, natural science, and Aristotelianism as in the days of the great Dominicans themselves. Again, it reveals the extent to which natural science, since the appearance of The Origin of Species, has tended to the opposite extreme.

As for historians of science, they have been rather scarcer of late than in the earlier years of the nine-teenth century, when the subject seems to have had a great vogue in France. Or at least the historians of science have been less sympathetic with the distant past. Perhaps the inclination has been to go almost as far toward the other pole of neglect as De Blainville went toward that of extollation. But the modern eulogies of the scientific attainments of Roger Bacon, supposed to be a thorn in the side of the medieval church and falsely regarded as its victim, and as the one lone scientific spirit of the middle ages, have been rather more absurd than the earlier praises of Albert, who was represented both as a strong pillar in the church and the backbone of medieval and Christian science. Indeed, the Histoire Littéraire, in the same passage which we a moment ago quoted against De Blainville, also states with probable justification that Albert did "more than any other doctor of his day" to introduce the natural sciences into the course of public and private studies, and that it was his taste for those subjects which won him his popular renown and the homage of scholars until the end of the seventeenth century. At no period, however, has Albert been entirely without defenders. Jessen in 1867 regarded him as an original natural scientist. Stadler in 1906 recognized that "he made many independent observations, perhaps even carried out experiments," and showed great interest in biology.

Coming back from the opinions of others concerning Albert to his own attitude towards natural science, it is to be noted that, while he may make all sorts of mistakes judged by modern standards, he does show unmistakable signs of the scientific spirit. This will become more apparent as we proceed, but for the present we may cite two examples of it, and these from a work based upon a pseudo-Aristotelian treatise and one which at first sight might seem quite superstitious and unscientific to the modern reader, since it is full of astrology, the De causis et proprietatibus elementorum et planetarum. In the first passage Albert repeats the justification of natural science against a narrow religious attitude which we heard from the lips of William of Conches in the previous century. When Albert finds that some men attribute the deluge simply to the divine will and believe that no other cause for it should be sought, he replies that he too ascribes it ultimately to the divine will, but that he believes that God acts through natural causes in the case of natural phenomena, and that, while he would not presume to search the causes of the divine will, he does feel free to investigate those natural causes which were the divine instruments. A little further on in the same chapter Albert declares that "it is not enough to know in terms of universals, but we seek to know each object's own peculiar characteristics, for this is the best and perfect kind of science."

This desire for concrete, specific, detailed, accurate knowledge concerning everything in nature is felt by Albert in other of his writings to be scarcely in the spirit of the Aristotelian natural philosophy which he follows and sets forth in his parallel treatises. In his work on animals a cleavage may be observed between those parts where Albert discusses the general natures and common characteristics of animals and seems to follow Aristotle rather closely, and those books where he lists and describes particular animals with numerous allusions to recent experience and considerable criticism of past authorities. At the beginning of his twenty-second book he apologizes for listing particular animals in alphabetical order, which is "not appropriate to philosophy," by saying that "we know we are debtors both to the wise and to the unlearned, and those things which are told in particular terms better instruct a rustic intelligence." But while this desire to describe particular objects precisely is felt by Albert to be not in accord with traditional philosophic methods of presentation, it is a desire which many of his contemporaries share with him. At the beginning of his sixth book on vegetables and plants, where particular herbs and trees are listed, he explains, "In this sixth book of vegetables we satisfy the curiosity of our students rather than philosophy, for philosophy cannot deal with particulars."

This healthy interest in nature and commendable curiosity concerning real things was not confined to Albert's students nor to "rustic intelligences." One has only to examine the sculpture of the great thirteenth century cathedrals to see that the craftsmen of the towns were close observers of the world of nature and that every artist was a naturalist too. In the foliage that twines about the capitals of the columns in French Gothic cathedrals it is easy to recognize, says M. Mâle, a large number of plants: "the plantain, arum, ranunculus, fern, clover, coladine, hepatica, columbine, cress, parsley, strawberry-plant, ivy, snapdragon, the flower of the broom and the leaf of the oak, a typically French collection of flowers loved from childhood." Mutatis mutandis, the same statement could be made concerning the carved vegetation that runs riot in Lincoln cathedral. "The thirteenth century sculptors sang their chant de mai. All the spring delights of the Middle Ages live again in their work—the exhilaration of Palm Sunday, the garlands of flowers, the bouquets fastened on the doors, the strewing of fresh herbs in the chapels, the magical flowers of the feast of Saint John—all the fleeting charm of those old-time springs and summers. The Middle Ages, so often said to have little love for nature, in point of fact gazed at every blade of grass with reverence." But it is not merely love of nature but scientific interest and accuracy that we see revealed in the sculptures of the cathedrals and in the note-book of the thirteenth century architect, Villard de Honnecourt, with its sketches of insect as well as animal life, of a lobster, two parroquets on a perch, the spirals of a snail's shell, a fly, a dragonfly, and a grasshopper, as well as a bear and a lion from life, and more familiar animals such as the cat and swan. The sculptors of gargoyles and chimeras were not content to reproduce existing animals but showed their command of animal anatomy by creating strange compound and hybrid monsters—one might almost say, evolving new species—which nevertheless have all the verisimilitude of copies from living forms. It was these breeders in stone, these Burbanks of the pencil, these Darwins with the chisel, who knew nature and had studied botany and zoology in a way superior to the scholar who simply pored over the works of Aristotle and Pliny. No wonder that Albert's students were curious about particular things.

But one is inclined to wonder whether the passage from the De causis et proprietatibus elementorum et planetarum, which we quoted first, may not have been written after the passages which we have quoted from his works on plants and animals, and whether Albert had come, thanks possibly to that same stimulating scientific curiosity of his students, to cease to apologize for the detailed description of particular objects as unphilosophical and to praise it as "the best and perfect kind of science." At any rate it is those portions of his works on animals, plants, and minerals which he devotes to such description of particular objects which possess most independent value, and it is perhaps also worth noting that Ptolemy of Lucca in looking back upon Albert's work seems not only to distinguish his writings on logic and theology from those on nature, but also to imply a distinction between Aristotle's natural philosophy and his "very well-known and most excellent contribution to the experimental knowledge of things of nature." Ptolemy seems to say Aristotle's contribution, but the credit really belongs largely to Albert and his students.

Pouchet was therefore not without justification in his sub-title, "Or Albertus Magnus and his Period Considered as the Beginning of the Experimental School." His distinguishing, however, three stages of scientific progress in the history of civilization—the first, Greek, characterized by observation, and represented especially by Aristotle; the second, Roman, marked by erudition and typified by Pliny; the third, medieval, distinguished by experimentation, and having Albertus Magnus and Roger Bacon as its two great representatives;—was rather too general and sweeping. Galen, for instance, was a great experimenter and the ancient Empirics put little trust in anything except experience. Albert himself, in discussing "the serious problem" whether life is possible in the Antipodes or southern hemisphere, states that "the most powerful kings and the most accomplished philosophers have labored over it from antiquity, the kings forsooth by experiment and the philosophers by rational inquiry." Moreover, neither Roger Bacon nor Albert can be shown to have done much experimenting of the sort, carefully planned and regulated, which is carried on in modern laboratories. Meyer in his History of Botany, although Albert was a great favorite with him, felt constrained to renounce the credit for purposive experimentation which Pouchet had given him. "How gladly would I see this crown also placed deservedly upon my favorite's head! … But I do not know of his undertaking an experiment in order to solve a physiological or physical problem in which he had a clearly defined purpose and the suitable materials at hand for carrying it out; his books on plants certainly do not contain a single one."

Albert's work on plants does contain, however, many passages in which he recognizes experience as a criterion of truth or gives the results of his personal observations. Such passages occur especially in the sixth book where he tries to satisfy his students' curiosity, but we may first note an earlier passage where he recommends "making conjectures and experiments" in order to learn the nature of trees in general and of each variety of tree, herb, fruit, and fungus in particular. Since, however, one can scarcely have personal experience of them all, it is also advisable to read the books which the experts (experti) of antiquity have written on such matters. But a mistrust of the assertions of others often accompanies Albert's reliance upon personal observation and experience. Like Galen in his work on medicinal simples, he explains in opening his sixth book that merely to list the names of plants found in existing books would fill a volume, and that he will limit his discussion to those native varieties "better known among us." Of some of these he has had personal experience; for the others he follows authors whom he has found unready to state anything unless it was proved by experience. For experience alone is reliable concerning particular natures. He cautions in regard to a tree which is said to save doves from serpents, "But this has not been sufficiently proved by certain experience, like the other facts which are written here, but is found in the writings of the ancients." Of another assertion he remarks, "But this is proved by no experience"; and of a third he says, "As some affirm, but I have not tested this myself."

Personal observation and experience are equally, if not more, noticeable in Albert's work on animals. He proposes to tell "what he knows by reason and what he sees by experience of the natures of animals"; he adds that science cannot be attained in all matters by demonstration, in some cases one must resort to conjecture. After listing various remedies for the infirmities of falcons from the work on falconry of the Emperor Frederick, he concludes, "Such are the medicines which one finds given for falcons and the experience of wise men, but the wise falconer will with time add to or subtract from them according to his own experience of what is beneficial to the state of health of the birds. For experience is the best teacher in all matters of this sort."

In the treatise on animals as in that on plants Albert's allusions to experience occur mainly in the last few books where he describes particular animals. Here he often says, "I have tested this," or "I and my associates have experienced," or "I have not experienced this," or "I have proved that this is not true." Like Alexander of Neckam he rejects the story that the beaver castrates itself in order to escape with its life from its hunters; Albert says that experience near his home has often disproved this. In discussing whales he restricts himself entirely to the results of his own observation, saying, "We pass over what the Ancients have written on this topic because their statements do not agree with experience." According to Pouchet Albert gives even more detailed information concerning whales than do the Norse sagas, and also includes animals of the north unknown to classical writers. He occasionally reveals his nationality by giving the German as well as the Latin names of animals, and he displays an acquaintance with the fauna of surrounding countries such as Norway, Sweden, Bohemia, and Carinthia. He asserts that there are no eels in the Danube and its tributaries, but that they abound in the other rivers of Germany. He tells of observing the habits of eagles in Livonia, or supports the account in Solinus of a monstrous beast with fore legs like human arms and hind legs like human legs by stating that he has seen both male and female of the species captured in the forests of Russia (Sclaviae). Of his wide travels and observation of natural phenomena we shall meet other examples as we proceed.

Albert has not only observed animal life widely, he has also performed experiments with animals as he apparently did not do with plants. He and his associates, for instance, have proved by experiment that a cicada goes on singing in its breast for a long time after its head has been cut off. He also proved to his satisfaction that the turtle, although a marine animal, would not drink sea water, unless possibly fresh water which flowed into the sea, by experimenting with a turtle in a vessel of water. He has heard it said that the ostrich eats and digests iron, but the many ostriches to whom he has offered the metal have consistently declined it, although they would devour with avidity stones and bones cut into small bits. Crude experiments these may be, but they are at least purposive.

Albert also often expresses doubt as to certain statements concerning animals on the ground that they have not been tested by experience, even if he has had no opportunity to disprove them. And he draws a sharp distinction between authors who state what they themselves have seen and tested and those who appear simply to repeat rumor or folk-lore. That there are any such birds as gryphons or griffins, he believes is affirmed in story-books (historiae) rather than supported by the experiments of philosophers or arguments of philosophy. The story found in the Physiologus of the pelican's restoring its young with its own blood he also considers as "read in story-books rather than proved philosophically by experience,"—a criticism which shows how mistaken those modern scholars have been who have declared the Physiologus and Bestiaries representative of the thirteenth century attitude towards nature. The accounts of harpies which one reads are also according to Albert "not based upon experience, but are the assertions of men of no great authority." They are said to be rapacious birds with crooked nails and human faces, and when a harpy meets a man in the desert it is said to kill him, but afterwards, when it sees by its reflection in the water that its own face is human, it grieves all the rest of its life for the man whom it has slain. "But these statements," says Albert, "have not been experienced and seem fabulous. Such tales are told especially by a certain Adelinus" (perhaps the Anglo-Saxon Aldhelm) "and Solinus and Jorach." Albert is particularly chary of accepting the assertions of these last two authors, assuring us, anent their statement that certain birds can fly unharmed through flames, "These philosophers tell many lies and I think that this is one of their lies." In yet other passages Albert calls one or the other of them a liar. He also sometimes rejects statements of Pliny, once classing him with Solinus among those who rehearse popular hearsay rather than disclose scientific experience.

Albert thus displays considerable independence in dealing with past authorities. Yet at times statements in earlier writers which seem absurd to us pass him unchallenged. He is far, for example, from rejecting all of Pliny's marvelous assertions. He still believes that the little fish eschinus can stop "a ship two hundred feet or more" in length by clinging to its keel, so that neither wind nor art nor violence can move it. And he adds something to Pliny's tale of hunters who make good their escape to their ship with the tiger's cubs by throwing them one at a time to the pursuing tigress, who takes each whelp back to her lair before returning to the pursuit of the hunters. Albert's emendation is that the hunters provide themselves with glass spheres which they roll one at a time towards the pursuing tigress. Seeing her own reflection on a small scale in the glass ball, she thinks it one of her cubs until she has vainly tried to give it milk, when she discovers the fraud and bounds after the hunters again. But a second and a third glass ball deceive her temporarily as before, and so the hunters reach their ship without having had to surrender any of the real cubs. This imputation of singular stupidity to the tigress should be kept in mind to set against other passages in medieval writers where almost human sagacity is ascribed to animals. Although in two or three preceding passages Albert has refuted the doctrine of spontaneous generation of animal life, he attributes the following passage to Pliny without adverse criticism. "There is a worm shaped like a star, as Pliny says, which shines like a star at night; but it never appears except when after great clouds it predicts clear weather. He says that there is so much rigid cold in this worm that it extinguishes fire like ice. And if a man's flesh is touched with its slime, all the hair falls off and what it touches decays. And he says that they beget nothing, nor is there male or female among them. Therefore they are generated from decaying matter." Albert also accepts the story of the poisoned maiden sent to Alexander the Great.

Albert also is unduly credulous of utterances about animals supposed to be based upon experience, although he cannot be called a mere empiricist, since he tries to test particular statements by the general laws concerning living beings which he has read in Aristotle or derived from his own experience and reflection. He denies, for example, Pliny's statement that other animals are attracted by the pleasant smell which the panther emits as it sleeps after overeating, on the ground that man is the only animal who is pleased or displeased by odors. But it would seem that some of the fishermen, fowlers, and hunters from whom he gleaned bits of zoological information were not so trustworthy as he imagined. He says that "a trustworthy person" told him that he saw in an eagle's nest three hundred ducks, over a hundred geese, about forty hares, and many large fish, all of which were required to satisfy the appetites of the young eagles. He also "heard from trustworthy persons" that a serpent with the virgin countenance of a beardless man "was slain in an island of Germany and there displayed in our times to all who wished to see it until the flesh putrefied." Such reports of mermaids and sea-serpents have still, however, a certain currency. Experienced hunters said that worms could be killed in any beast by suspending from its neck a strip of citron (sticados citrinum) immediately after it had been dried. German artificers of Albert's day told him that the hyena bore a gem in its eyes, or more truly in its forehead. Albert sometimes has a tall story of his own to tell. At Cologne in the presence of himself and many associates a little girl of perhaps three years was exhibited who, as soon as she was released from her mother's hands, ran to the corners of the room searching for spiders, "and ate them all large and small, and flourished on this diet and greatly preferred it to all other food." Albert also learned by personal experience that moles gladly eat frogs and toads. For once he saw a mole who held by the foot a big toad which "cried loudly because of the mole's bite." He also found by experience that both frogs and toads would eat a dead mole. In affirming that the custom of killing off the old men is still prevalent within the borders of Saxony and Poland, Albert says, "As I have seen with my own eyes"; but really all that he has seen is the graves of their fathers which the sons have shown to him.

Albert's general attitude towards past authorities and present experience remains the same in his treatise on minerals. He will give the names of the important gems and state their virtues as known from authorities and experience, but he will not repeat everything that has been said about precious stones because it is not profitable for science. "For natural science is not simply receiving what one is told, but the investigation of causes in natural phenomena." Concerning metals, too, he intends to state "rationally either what has been handed down by the philosophers or what I myself have experienced." He adds that once he wandered far in exile to places rich in mines in order that he might test the natures of metals. "And for this same reason I investigated the transmutation of metals among the alchemists, in order that I might observe something of the nature and characteristics of the metals." In a later chapter he alludes to workers in copper "in our parts, namely, Paris and Cologne, and in other places where I have been and seen things tested by experience." Fui et vidi experiri, such is Albert the Great's peaceful paraphrase, probably unintentional, for warring Caesar's Veni, vidi, vici.

Again, also, in the treatise on minerals, reliance upon experience proves to be no sure guarantee against incorrect notions, credulity, and unquestioning trust in authority. Albert still repeats the old notion that "adamant," hard as it is, is softened and dissolved by the blood and flesh of a goat, especially if the goat for some time before has been fed on a diet of certain herbs and wine. He adds that this property of goat's blood makes it beneficial for sufferers from stone in the bladder. Albert repeats with a qualifying "It is said" the statement that the emerald comes from the nests of gryphons or griffins, but he does not stop to deny the existence of those birds, as we have heard him do elsewhere. He adds, however, as to the source of the emerald that "a truthful and curious experimenter coming from Greece" had said that it was produced in rocks under the sea. This expression, "curious experimenter" (curiosus experimentator), or perhaps better "inquisitive observer," Albert also applied to one of his associates who saw Frederick II's peculiar magnet. In the present discussion of the emerald he adds that experience in his own time has proved that this stone, "if good and true," cannot endure sexual intercourse, so that the reigning king of Hungary, who was wearing an emerald upon his finger when he went in to his wife, broke it into three pieces. "And that is probably why they say that this stone inclines its wearer to chastity."

Albert, however, had told as a personal experience a stranger tale than this of an emerald in his work on vegetables and plants in order to illustrate "the many effects of stones and plants which are known by experience and by which wonders are worked." But as a matter of fact, the incident is concerned not with an emerald and a plant, but an emerald and a toad, an animal which one would infer was in Albert's day often the subject of experiment.

"An emerald was recently seen among us, small in size but marvelous in beauty. When its virtue was to be tested, someone stepped forth and said that, if a circle was made about a toad with the emerald and then the stone was set before the toad's eyes, one of two things would happen. Either the stone, if of weak virtue, would be broken by the gaze of the toad; or the toad would burst, if the stone was possessed of full natural vigor. Without delay things were arranged as he bade; and after a short lapse of time, during which the toad kept its eye unswervingly upon the gem, the latter began to crack like a nut and a portion of it flew from the ring. Then the toad, which had stood immovable hitherto, withdrew as if it had been freed from the influence of the gem."

In the incident just narrated Albert was perhaps tricked by some traveling magician. But let us conclude our discussion of his general scientific method by some more rational instances of personal observation and experience. In his treatise on meteorology his discussion of the rainbow, which occupies some twenty-four pages of Borgnet's text, is especially based upon experience and full of allusions to it—a very interesting fact in view of the large space which the discussion of the rainbow occupies in Roger Bacon's better known eulogy of experimental science. Albert recounts his own observations when sailing over great waves or when looking down from the top of a castle built upon a high mountain, "and the time when this was seen was in the morning after a rainy night, and it was in the autumn with the sun in the sign of Virgo." Albert takes exception to Aristotle's assertion that rainbows caused by the moon at night appear only twice in fifty years. He and many others have seen a bow at night, and "truthful experimenters have found by experience" (veridici experimentatores experti sunt) that a rainbow has appeared twice at night in the same year. Nor can Albert conceive of any astronomical reason why it should appear only twice in fifty years. "And so I think that Aristotle stated this from the opinions of others and not from the truth of demonstration or experience, while those facts which have been adduced against his statement have been experienced beyond a doubt by myself and by other reliable investigators associated with me." The very chapter headings of this portion of Albert's treatise suggest an antithesis between the ancient authorities and recent experimental investigation, for instance: "Of the Iris of the Moon and what Ancients have said of it and what Moderns have tested by experience," and "A Digression stating Seneca's views concerning virgae and experiments with certain arcs seen in modern times." Thus while Albert of course believes that the statements of many of his authorities are based upon experience, he seems to feel that he and his associates have founded an important modern school for the investigation of nature at first hand. We may choose to regard it as a mere school of observation, but he dignifies its members by the title of experimentatores. Again therefore we may admit that Pouchet was not unjustified in associating Albert with the modern experimental school.

At the close of his story of the toad and the emerald Albert adds that there are many other such virtues of stones and plants which are learned by experience, and that magicians investigate the same and work wonders by them. It is therefore quite appropriate for us to turn directly from his attitude to experimental method to his conception of magic. Like William of Auvergne he hints at an association between the two. His pupil and contemporary, Ulrich Engelbert of Strasburg, actually called him "expert in magic."

In his Life of Albert Peter of Prussia not only is evidently concerned to make him out a saint as well as a scientist, telling of his devotion to the Eucharist and the Virgin Mary and the wood of the Holy Cross and of the miraculous visions which he had from childhood, in which the Virgin and the Apostle Paul appeared to him, and how he advanced more in knowledge by prayer than by study and labor, and that he read the Psalter through daily. He also devotes a number of chapters to a defense of Albert against the charge of having indulged in occult sciences, and of having been "too curious concerning natural phenomena." Peter explains that many superstitions were rife in Albert's time and that necromancers were fascinating the people by their false miracles, and pretending that their sorcery was worked by the sciences of astronomy, mathematics, and alchemy. It was therefore essential that some man who was equally learned and devout should thoroughly examine these sciences, proving what was good in them and rejecting what was bad. Peter is inclined to be disingenuous in stating Albert's attitude toward some of the occult sciences, especially the engraving of stones with images according to the aspects of the stars, which he misrepresents Albert as prohibiting, whereas Albert really calls it a good doctrine, as we shall show later. Peter however states "how useful it is to know natural and occult phenomena in the nature of things, and that those who write about such things are to be praised for it." Also "that it is useful and necessary to know the facts of nature even if they are indecent." Later on, towards the close of his book, Peter denies various feats of magic that by his time had come to be popularly recounted of Albert, and then does his best to make up for the subtracted marvels by himself inventing many pious miracles in which he would have us believe Albert was concerned.

The learned Trithemius (1462-1516), abbot of Sponheim, in a letter to John Westenburgh in which he defends himself against the charge of magic, admits that he "cannot say that he is entirely ignorant of natural magic," a form of wisdom which he regards very highly; and adduces in his justification the example of "Albertus Magnus, that most learned man and among the saints truly most saintly, of the profoundest intellect, worthy of eternal memory, who scrutinized the depths of natural philosophy, and learned to know marvels unheard of by others." Even to this day, continues Trithemius, he is unjustly regarded by the unlearned as a magician and devotee of superstition. For he was not ignorant of the magic of nature, and he had innocently read and mastered a great number of superstitious books by depraved men. For not the knowledge but the practice of evil is evil. Trithemius admits that he himself has read many books of superstitious and even diabolical magic, but contends that this is necessary, if one is to learn to distinguish natural from illicit magic.

The brief but sane estimate of Albertus Magnus published eighty years ago in the Histoire Littéraire de la France, from which we have already had occasion to quote regarding his importance in the history of natural science, mentions the efforts of Trithemius and Naudé to defend him from the charge of magic, but adds that even his panegyrists have called him "great in magic, greater in philosophy, greatest in theology," and agrees that he frequently shows a leaning towards the occult sciences. "He is an alchemist, he is an astrologer, he believes in enchantments; he delights like most savants of his age in explaining all phenomena that surprise him by supernatural causes." This rough characterization contains much truth, although it is hardly true that Albert gave supernatural explanations for strange natural phenomena. Rather he believed in occult forces and marvels in nature which we no longer credit. We also have already stated it as our opinion that he was really much greater as a natural scientist than as a theologian. But we have now to examine what grounds there are for calling him magnus in magia, and in magicis expertus.

Magic is often mentioned by Albert, both in his Biblical and Aristotelian commentaries, both in his theological writings and his works on natural science. Some references to magic arts, occurring chiefly in the Biblical commentaries, are too brief, incidental, and perfunctory to afford any particular information. The other passages seem scarcely consistent with one another and will require separate treatment. We shall first consider those in which Albert more or less adheres to the traditional Christian attitude of condemnation of magic as criminal and dealing with demons, of recognition of its marvels but jealous differentiation of them from divine miracle. It should be observed that all such passages occur in his theological writings and that in them he does little more than rehearse opinions which we have already encountered in the writings of the early Christian fathers with a few additional citations from books of necromancy or from Arabic works on natural science such as those of Algazel and Avicenna.

Albert has no doubt either in his scientific or religious writings that marvels can be worked by magic. It is true that one of its departments, praestigia, has to do with illusions and juggleries in which things are made to appear to exist which have no reality. But it also performs actual transformations. But even the actual performances of magic are deceptive in that demons by their means lead human souls astray, which is far worse than merely to deceive the eye.

Albert affirms in his theological Summa that it is the consensus of opinion that magic is due to demons. "For the saints expressly say so, and it is the common opinion of all persons, and it is taught in that part of necromancy which deals with images and rings and mirrors of Venus and seals of demons by Achot Graecus and Grema of Babylon and Hermes of Egypt, and invocations for this purpose are described in the book of Hermogenes and Philetus, the necromancers, and in the book called the Almandel of Solomon." In his Commentary on the Sentences Albert declares that to make use of "magic virtues" is evil and apostasy from the Faith, whether one openly resorts to "invocations, conjurations, sacrifices, suffumigations, and adorations," or to some simple operation which none the less requires demon aid for its performance. One must beware even of "mathematical virtues," that is, of astrological forces, especially in "images, rings, mirrors, and characters," lest the practice of idolatry be introduced. In commenting upon the passage in the gospel where the Pharisees accuse Christ of casting out demons through the prince of demons, Albert admits that necromancers are able to cast out demons and to restrain them from doing external damage, but holds that they cannot like Christ restrain the evil spirits from inciting inward sin.

Albert will not admit, however, that the marvels of magic compare with divine miracles. For one thing, feats of magic do not even happen as instantaneously as miracles, although they occur much more rapidly than the ordinary processes of nature. But except for this difference in speed the works of magic can usually be explained as the product of natural forces, and by the fact that the demons are aided in their operations by the influence of the stars. To change rods into snakes, for instance, as Pharaoh's magicians did, is simply hastening the process by which worms generate in decaying trees. Indeed, Albert is inclined to believe that the demons "produce no permanent substantial form that would not easily be produced by putrefaction." The magic power of fascination is after all only analogous to the virtue of the sapphire in curing ulcers or of the emerald in restraining sexual passion. Albert adds the comforting thought that neither fascination nor the magic art can harm anyone who has firm faith in God, but for us the most important thing to note is that even in his theological writings he has associated magic with natural forces and the stars as well as with demons. In this he resembles William of Auvergne rather than the early Christian fathers.

Like some other Christian commentators, Albert exempts the Magi of the gospel story, who followed the star to Bethlehem, from the category of magicians in the evil sense that we have just heard him define magic. In his commentary upon the gospel by Matthew he asserts that "the Magi are not sorcerers (malefici) as some wrongly think." He also affirms that there is a difference between a Magus and a mathematicus or an enchanter or necromancer or ariolus or aruspex or diviner. Like Isidore Albert adopts the incorrect etymology of connecting Magus and magnus. But for him the Magi are not so called on account of the magnitude of their sins. "Etymologically the Magi are great men" whose knowledge of, or conjecture from, the inevitable processes of cause and effect in nature often enables them to predict or produce marvels of nature. In his commentary on the Book of Daniel Albert quotes Jerome's similar description of them as "masters who philosophize about the universe; moreover, the Magi are more particularly called astronomers who search the future in the stars." It is interesting to note that this view of the Magi still persists among Roman Catholics; the recent Catholic Encyclopedia still insists concerning the wise men who came to Bethlehem, "Neither were they magicians: the good meaning of mágoi, though found nowhere else in the Bible, is demanded by the context of the second chapter of Matthew." But here is a still more interesting point to note: Albertus Magnus does not deny that the Magi were magicians. To contend that Magi were not magi was a contradiction of terms that was probably too much for his common sense. All that he tries to do is to exculpate them from the practice of those particular evil, superstitious, and diabolical occult arts which Isidore and others had included in their definitions of magic. From evil witchcraft and necromancy and fatalistic astrology, from augury and liver divination, from the arts of sortilegi and pythones, of enchanters "who by means of certain incantations perform certain feats with beasts or herbs or stones or images," or of diviners who employ geomancy or "the chance of fire" or hydromancy or aerimancy: from all such practices he acquits them. "They were not devoted to any of these arts, but only to magic as it has been described. And this is praiseworthy." Thus Albert not merely defends the Magi, he praises magic; and we begin to see the fitness of the epithet, Magnus in magia, as applied to him.

But how does this praiseworthy magic differ from the magic which he condemned in his Summa and commentary on the Sentences? Presumably in that its objects are good not evil, and that it does not make any use of demons. It would seem to resemble closely the natural magic of William of Auvergne. It is like evil magic in that both employ the forces of nature and the influences of the stars, but it is unlike it in that it employs them exclusively and is free from any resort to demons and also apparently from the use of incantations or the superstitious devices of geomancers and other diviners.

If in his theological writings Albert thus distinguishes two varieties of magic, one good and one evil, one demoniacal and one natural, we need not be surprised if in his scientific treatises, where he is influenced mainly by Arabian astrology, the pseudo-Aristotelian treatises, the Hermetic literature, and other such writings rather than by patristic literature, he introduces yet a third conception of magic, which scarcely agrees with either of the others and yet has features in common with both. He nowhere in his commentaries on Aristotle or other works of natural science really stops and discusses magic at any length. But there are a number of brief and incidental allusions to it which imply that it is a distinct and definite branch of knowledge of which, although he himself does not treat, he gives no sign of disapproval. He also cites even enchanters and necromancers without offering any apology, and now seems to regard as sub-divisions of magic those occult arts from which we have just heard him exculpate the Magi.

In his treatise on animals Albert states that anointing a sleeper's temples with the blood of a hoopoe makes him see terrible dreams, and that enchanters value highly the brain, tongue, and heart of this bird. He adds, "But we shall not discuss this matter here, for the investigation of it belongs to another science,"—presumably to magic. In his treatise on plants he says that certain herbs seem to have "divine effects" which those who study magic follow up further. Examples are the betony, said to confer the power of divination, the verbena, used as a love charm, and the herb meropis, supposed to open closed seas, and many other such plants listed in the books of incantations of Hermes the philosopher and of Costa ben Luca the philosopher and in the books of physical ligatures. "Enchanter" (Incantator,) apparently the author or title of a book, is cited more than once for the virtues of herbs, and what enchanters in general say is also mentioned. "According to the testimony of the praestigia of the magi" the juice of a certain herb drunk in water makes a person do or say whatever the magician says or does. Students of magic believe that the seed of another herb extinguishes lust. Necromancers avow that betony indicates the future when plucked with an adjuration of Aesculapius, and students of necromancy say that a man invoking demons should have a character painted on him with the herb Jusquiam, and that gods invoked by characters and seals and sacrifices present themselves more readily if frankincense is offered them. Such passages seem to indicate that Albert regarded occult virtues as largely the concern of magic, but that at least in necromancy the invocation of gods and demons also enters.

Many allusions to magic occur in Albert's treatise on minerals, as the especially marvelous powers attributed to gems in antiquity might well lead us to expect. The magi, he tells us, make much use of the stone diacodos, which is said to excite phantasms but loses its virtue if it touches a corpse. But such things do not come within Albert's present scope; he refers the reader for further information to the books of magic of Hermes, Ptolemy, and Thebith ben Chorath. The stone magnet is also stated in the magic books to have a marvelous power of producing phantasms, especially if consecrated with an adjuration and a character.

Albert twice assures us that the "prodigious and marvelous" powers of stones, and more particularly of images and seals engraved on stones, cannot be really understood without a knowledge of the three other sciences of magic, necromancy, and astrology. He therefore will not in this treatise on minerals discuss the subject as fully as he might, "since those powers cannot be proved by physical laws (principiis physicis,) but require a knowledge of astronomy and magic and the necromantic sciences, which should be considered in other treatises." For the reason why gems were first so engraved he refers his readers to "the science of the magi which Magor Graecus and Germa of Babylon and Hermes the Egyptian were among the first to perfect, and in which later wise Ptolemy was a marvelous light and Geber of Spain; Tebith, too, handed down a full treatment of the art." And in this science it is a fundamental principle that all things produced by nature or art are influenced by celestial virtues. Thus we comprehend the close connection of astrology and magic. As for necromancy, the third "science" involved, Albert's associates are curious to know the doctrine of images even if it is necromancy, and Albert does not hesitate to assure them that it is a good doctrine in any case. Yet in his theological writings he not only condemned necromancy, but declared the art of images to be evil "because it inclines to idolatry by imputing divinity to the stars, and … is employed for idle or evil ends."

Albert again refers to magic in his discussion of alchemy in the treatise on minerals, where he not only cites Hermes a great deal but refers to writings by Avicenna on magic and alchemy. Albert holds that it is not the business of a physical or natural scientist (physicus) to determine concerning the transmutation of metals; that is the affair of the art of alchemy, which thus seems to lie outside the field of natural science upon the borders of magic. Similarly the problem in what places and mountains and by what signs metals are discovered falls partly within the sphere of natural science and partly belongs to that magical science which has to do with finding hidden treasure. Albert perhaps has the employment of the divining rod in mind.

The occult virtue of the human mind is another matter which Albert seems inclined to place within the field of magic. In the treatise on minerals he remarks that whether fascination is true or not is a question for magic to settle, and in his On Sleep and Waking he cites Avicenna and Algazel as adducing "fascination and magic virtues" as examples of occult influence exerted by one man over another. It will be remembered that he cited the same authors anent fascination in his Commentary on the Sentences, but there denied that fascination or magic could harm anyone who had firm faith in God, although he illustrated the possibility of potent human occult virtue exercised at will by the marvelous virtues exerted constantly by the sapphire and emerald. Peter of Prussia gives us to understand that Albert's belief was that fascination did not operate naturally but by the aid of demons; nevertheless certain men are generated at rare intervals who work marvels like the twins in Germany in Albert's time at whose approach bolts would open.

Albert also regards the interpretation of dreams as especially the affair of magic. In one passage of On Sleep and Waking he grants that probably the art of interpreting dreams cannot be acquired without a knowledge of magic and "astronomy." In a second passage he speaks of the magicians as teaching the interpretation of dreams and the "astronomers" as talking of signs of prophecies, but not the sort of prophecy accepted among theologians. In a third passage he defines the kind of dreams "which wise men interpret and for which was invented the art of interpretation in the magical sciences." Albert seems to have no particular objection, either moral or religious, to the interpretation of dreams, even if it is a branch of magic. Rather he censures Aristotle and other philosophers for not having investigated this side of the subject further, and he thinks that by physical science alone one can at least determine what sort of dreams are of value for purposes of divination and are susceptible to interpretation. Magicians make great use not only of dreams but also of visions seen when one is awake but with the senses distracted. The magicians indeed specialize in potions which clog and stupefy the senses, and thereby produce apparitions by means of which they predict the future.

In this same treatise On Sleep and Waking Albert lists together "the astronomer and augur and magician and interpreter of dreams and visions and every such diviner." He admits that almost all men of this type delight in deception and are poorly educated and confuse what is contingent with what is necessary, but he insists that "the defect is not in the science but in those who abuse it." Thus magic and divination in general are closely associated.

This last passage, like the connecting of enchanters and necromancers with magic which we have noted in a previous paragraph, is hard to reconcile with the passage in his commentary upon the Gospel of Matthew where Albert separated the Magi and magic from diviners, enchanters, necromancers, and their arts. So far as mere classification is concerned, Albert's references to magic in his scientific writings are in closer accord with his discussion of magic in the Summa and Sentences, where too he associated magic with the stars, with occult virtues, with fascination, and with images. But the emphasis which he there laid upon the evil character of magic and its connection with demons is now almost entirely lacking. Our attention is rather being continually called to how closely magic, or at least some parts of it, border upon natural science and astronomy. And yet we are also always being reminded that magic, although itself a "science," is essentially different in methods and results from natural science or at least from what Albert calls "physical science." Overlapping both these fields, apparently, and yet rather distinct from both in Albert's thought, is the great subject of "astronomy" which includes both the genuine natural science and the various vagaries of astrology. It is all like some map of a feudal area where certain fiefs owe varying degrees of fealty to, or are claimed by, several lords and where the frontiers are loose, fluctuating, and uncertain. Perhaps the rule of the stars can be made to account for almost everything in natural science or in magic, but Albert seems inclined to leave room for the independent action of divine power, the demons, and the human mind and will. … [In conclusion] let us make the one further observation that while Albert describes magic differently and even inconsistently in different passages, it is evident enough that he is trying to describe the same thing all the time.