Fourteenth-century philosopher; nicknamed Albertus Parvus, Albertutius, and Albertilla by the Italian Scholastics of the Renaissance. In 1351 he passed the first examination ( determinatio) at the University of Paris, where he figured as a member of the English Nation. In the same year he was elected procurator of the English Nation; in 1353 rector of the university; in 1361, collector of dues of the English Nation; in 1358 he had been one of the representatives of this Nation in the concordat with the Picard Nation. In 1361 the English Nation suggested him for the suburban parish of Sts. Cosmas and Damian, which depended on the university. In 1368 he still belonged to the faculty of arts at the University of Paris, where he compiled his questions on Aristotle's "De Cælo et Mundo". Owing to their common surname of Albert of Saxony, Albert of Helmstädt has often been confused with Albert, son of Bernard the Rich, of Ricmestorp (Diocese of Halberstädt). The latter's name occurs for the first time in 1362 among the masters of the English Nation at the University of Paris; in 1363 he was rector of the university; in 1365 Rudolf, Duke of Austria, sent him as ambassador to Pope Urban V. In that same year the University of Vienna was founded and through the influence of Rudolf, Albert of Ricmestorp was elected first rector. He was consequently appointed a canon of Hildesheim and (21 Oct., 1366) Bishop of Halberstädt.

All the works which we possess under the name of Albert of Saxony belong to Albert of Helmstädt. Some were devoted to logic, others to physics. The study of these books is admirably calculated to inform us on the views current at the University of Paris in the middle of the fourteenth century. The treatises on logic written by Albert of Saxony are devoted to the detailed and subtle dialectic which at the end of the thirteenth century Petrus Hispanus had introduced into the teaching of the Parisian Scholasticism, but they present neither the disorder nor the multitude of empty quibbles which about the same time were introduced into the instruction at the University of Oxford and which became predominant there under the influence of William Heytesbury. Albert of Saxony's treatises on physics consist of a "Tractatus proportionum" and questions on Aristotle's "Physics", "De Coelo", and "De generatione et corruptione". These contain, in a clear, precise, and concise form, an explanation of numerous ideas which exercised great influence on the development of modern science, which ideas, however, were not wholly personal to Albert of Helmstädt, many of the most important of them being derived from his master, Jean Buridan. He abandoned the old Peripatetic dynamics which ascribed the movement of projectiles to disturbed air. With Buridan he placed the cause of this movement in an impetus put into the projectile by the person who threw it; the part he assigned to this impetus is very like that which we now attribute to living force. With Buridan he considered that the heavens were not moved by intelligences, but, like projectiles, by the impetus which God gave them when He created them. With Buridan he saw in the increase of impetus the reason of the acceleration in the fall of a heavy body. He further taught that the velocity of a falling weight increased in proportion either to the space traversed from the beginning of the fall or to the time elapsed, but he did not decide between these two.

The equilibrium of the earth and seas is the subject of a favourite theory of Albert's. The entire terrestrial element is in equilibrium when its centre of gravity coincides with the centre of the world. Moreover, the terrestrial mass has not everywhere the same density, so that its centre of gravity does not coincide with the centre of its figure. Thus the lightest part of the earth is more distant from the centre of gravity of the earth than the heaviest part. The erosion produced by rivers constantly draws terrestrial particles from the continents to the bosom of the sea. This erosion, which, by scooping out the valleys, has shaped the mountains, constantly displaces the centre of gravity of the terrestrial mass, and this mass is in motion to bring back the centre of gravity of the earth to the centre of its figure. Through this motion the submerged portions of the earth constantly push upwards the emerged parts, which are incessantly being eaten away and afterwards replaced by the submerged parts. At the beginning of the sixteenth century this theory of Albert's strongly attracted the attention of Leonardo da Vinci, and it was to confirm it that he devoted himself to numerous observations of fossils. Albert of Saxony, moreover, ascribed the precession of the equinoxes to the similar very slow movement of the terrestrial element.

His "Tractatus proportionum" went through eleven editions; one bears no date or indication of its origin; three were issued at Padua in 1482, 1484, and 1487; four were printed at Venice in 1487, 1494, and twice in 1496; two were printed at Venice in 1502 and 1506; finally, an edition without date or printer's name was issued at Paris. The "Subtilisimæ quæstiones super octo libros Physicorum" were printed at Padua in 1493, at Venice in 1504 and 1516. The "Quæstiones in Aristotelis libros de Coelo et Mundo" were published at Pavia in 1481, at Venice in 1492 and 1497. The "Quæstiones in libros de generatione et corruptione", with the commentaries and questions which Gilles of Rome and Marsilius of Inghen had compiled on the same subject, were printed at Venice in 1504, 1505, and 1518. Albert's "Quæstiones" on the Physics, the "De Coelo", and the "De generatione", followed by the questions of Thémon and of Buridan on the "De anima", were printed in Paris in 1516 and 1518. The "Quæstiones super libros posteriorum Aristotelis" were printed at Venice in 1497; the "Sophismata" at Paris in 1489; the "Tractatus obligationum" at Lyons in 1498; the two last-named works, joined with the "Insolubilia", were published at Paris in 1490, 1495, and at an unknown date. In 1496 was printed at Bologna the "Expositio aurea et admodum utilis super artem veterem, edita per venerabilem inceptorem fratrem Gulielmum de Ocham cum questionibus Alberti parvi de Saxonia". Finally, the "Logica Albertucii" was edited at Venice in 1522.

PRANTL, Geschichte der Logik im Abendlande, IV (Leipzig, 1867); THUROT, Recherches historiques sur le principe d'Archimède, 3rd article in Revue archéologique, new series, XIX (1869); BONCOMPAGNI, Intorno al Tractatus proportionum di Alberto di Sassonia in Bulletino di Bibliografia e di Storia delle Scienze matematiche e fisiche, IV (1871); JACOLI, Intorno ad un comento di Benedetto Vittori, medico Faentino, al Tractatus proportionum di Alberto di Sassonia in ibid.; SUTER, Der Tractatus, "De quadratura circuli" des Albertus de Saxonia in Zeitschrift für Mathematik und Physik, XXIX (1884); SUTER, Die Questio "De proportione dyametri quadrati ad costam ejusdem" des Albertus de Saxonia, ibid., XXXII (1887); DUHEM, Les origines de la statique, II (Paris, 1906); IDEM, Etudes sur Lèonard de Vinci, ceux qu'il a lus et ceux qui l'ont lu, 1st ser. (Paris, 1906); 2nd ser. (Paris, 1909); 3rd ser. (in press).

PIERRE DUHEM