Telesius, Bernard

, a modern philosopher, was born at Naples in 1508, and received the first part of his education at Milan, where he acquired a perfect knowledge of the Latin and Greek languages. After passing two years at Rome, where he made great proficiency in polite learning, he removed to Padua, and applied with indefatigable assiduity to the study of mathematics and philosophy. He very judiciously employed mathematical learning in explaining and establishing the laws of physics, and was particularly successful in investigating truths before unknown in the doctrine of optics. Accustomed to mathematical accuracy, he grew dissatisfied with the conjectural explanation of natural appearances given by Aristotle, and expressed great surprise that this philosopher should have been, for so many ages, followed in his numerous errors | by so many learned men, by whole nations, and almost by the whole human race. He pursued his researches with great ingenuity as well as freedom, and wrote two books “On Nature,” in which he attempted to overturn the physical doctrine of the Peripatetic school, and to explain the phenomena of the material world upon new principles. When this treatise was first published at Rome, it obtained great and unexpected applause, and Telesius was prevailed upon by the importunity of his friends at Naples, to open a school of philosophy in that city. The Telesian school soon became famous, not only for the number of its pupils, but for the abilities of its professors, who distinguished themselves by their bold opposition to the doctrines of Aristotle, and by the judicious manner in which they distributed their labours, in order to enlarge the boundaries of natural knowledge. The founder of the school was highly esteemed by all who were desirous of studying nature rather than dialectics; and he was patronized by several great men, particularly by Ferdinand duke of Nuceri. But his popularity soon awakened the jealousy and envy of the monks, who loaded him and his school with calumny, for no other offence than that he ventured to call in question the authority of Aristotle. The vexations which he suffered from this quarter brought on a bilious disorder, which, in 1588, terminated in his death.

Although, during the life of Telesius, his innovations were patiently borne, both in Rome and Naples, after his death his writings were proscribed in the Index Expurgatorius of the inquisition. Notwithstanding which, his philosophy continued to have many admirers, and his works were republished at Venice in 1590, by his friend Antonius Persius, who also wrote a compendium of his philosophy in the vernacular tongue. Besides his principal work, De Natura Rerum, “On the Nature of Things,” he wrote on the air, the sea, comets, the milky way, the rainbow, colours, respiration, sleep, and other subjects. Lord Bacon has given a brief explanation of the philosophy of Telesius.

The physical system, which Telesius attempted to substitute in the room of the subtleties and fictions of the Stagyrite, was founded upon the Parmenidean doctrine, that the first principles in nature, by means of which all natural phenomena are produced, are cold and heat. The sum of his theory is this matter, which is in itself incapable of | action, and admits neither of increase nor diminution, is acted upon by two contrary incorporeal principles, heat and cold. From the perpetual opposition of these, arises the several forms in nature; the prevalence of cold in the lower regions producing the earth and terrestrial bodies; and that of heat in the superior, the heavens and celestial bodies. All the changes of natural bodies are owing to this conflict; and according to the degree in which each principle prevails, are the different degrees of density, resistance, opacity, moisture, dryness, &c. which are found in different substances. In the heavens heat has its fixed residence, without any opposition from the contrary principle: and within the earth, and in the abyss of the sea, cold remains undisturbed, heat not being able to penetrate thither. At the borders of each of these regions, that contest between the opposite principles begins, which is carried on through all the intermediate space. All animal and vegetable life is from God. This system, which Telesius evidently borrowed from Parmenides, is but a baseless fabric raised upon a fanciful conversion of mere attributes and properties into substantial principles, and did not long survive its author, who would have deserved credit for the boldness of his attack upon the principles of Aristotle, had he avoided constructing a new system of natural philosophy, liable to the same objection which he had brought against that of Aristotle. ¹