LEIBNITZ, GOTTFRIED WILHELM, was born on the 3rd of July 1646, at Leipzig, where his father (Friedrich) was professor of jurisprudence. Having lost his father at the age of six years, he was placed at the school of St, Nicholas, in his native city, from whloh he was removed in his fifteenth year to the university of the same place. Although law was his principal study, he combined the legal lessons of the elder Thomasius with those of Kuhn in mathematics, and applied at the same time with great diligence to philology, history, and, in short, to every branch of knowledge. Of ancient writers, Plato, Aristotle, and the Pythagoreans seem to have exorcised the greatest influence on his mental character, and his profound know ledge of their writings has furnished many au element in his own philosophy, while it suggested a wish, as bold as it was Impracticable, of reconciling their several systems and combining them into one consistent whole. After further prosecuting his mathematical studies at Jena under Erhard Weigel, Leibnitz returned to Leipzig, where ho passed successively to the degrees of Bachelor and Master iu Philo sophy. On the latter occasion (1664) be read his treatise 'De Principio ludividuationie, in which he took the side of the nominalists against the realists. His pursuits at this time were chiefly of a mathematical and juristical character. In 1664 appeared the treatise 'Qumstiones Philosophic= ex Jure collectre,' which was followed in the next year by the 'Doctrine Conditionuni.' The treatise 'Do Arte Combinatoria' was published in 1666. This important and remarkable work contained a new method of combining numbers and ideas, and was Intended to exhibit the scientific advan tages of a more extensive design, of which it was only a particular application. This general design, which is sketched in the ' Historia et Conimendatio Lingure Characteristicre Universalis' (' Posthumous Works,' by Itasp6, p. 535), was the invention of an alphabet of ideas, to consist of the most simple elements or characters of thought, by which every possible combinatiou of ideals might be es pressed ; so that by analysis or synthesis the proof or discovery of all truth might be possible. Notwithstanding such early proofs of his genius and talents, Leibniz was refused a dispensation of age which be had asked fur at Leipzig iu order to take the degree of Doctor of Laws, which however he obtained at Altorf. His exercise on this occasion was published under the title' De Casibus in Jure Perplesis,' which was everywhere received with approbation. Declining a professorship hero
offered to him, In all probability from a distaste for a scholutio life, he proceeded to Nilrnberg, where he joined a society of adepts in the pursuit of the philosopher's stove, and, being appointed secretary, was selected to compile their most famous works on Alchemy. For such an occupation he is said to have proved his fitness by composing a letter, requesting the honour of admission, so completely after the style of the alchemists, that it was unintelligible even to himself. From these pursuita he was removed by the Baron von Beizeiburg, chancellor to the Elector of Mainz, who invited him to proceed to Frankfurt in the capacity of councillor of state and assessor of the chamber of justice. He here composed tho valuable and important essay 'Nova Methodus docendi discendique Jurie, cum subjecto csta logo desideratorum.' At this time Leibnitz began to prosecute the study of philosophy with greater energy, and to extend his fame to foreign countries by the republication of the work of Nizolius, 'De verbs l'rincipiis at vera Redone Philosophandi,' to which he contributed many philosophical notes and treatises. To this date belong two original compositions which are remarkable for their boldness of views, and as containing the germ of his later philosophical system.
Of these two works, the ' Theoria Motus Concreti' was communicated to the Royal Society of London, and the Theoria Motu Abstracti ' to the Academy of Sciences of iaris. The latter city he first visited in 1672, In company with the son of his patron, and there formed the acquaintance of the most learned and distinguished men of the age— among others, of Malebranche, Cassini, and Iluyghens, whose work on the oscillation of the pendulum attracted Leibuitz to the pursuit of the higher mathematics. Leibnitz next proceeded to London, where he became personally acquainted with Newton, Oldenburg, Wallis, Boyle, and others, with many of whom he had previously maintained an active correspondence. Upon the death of the Elector of Mainz, he received from the Duke of Brunswick Liineburg the appointment of liofrath and Royal Librarian, with permission however to travel at pleasure. Ho accordingly visited London a second time, in order to make known his mathematical studies and to exhibit his arithmetical machine. This machine, either an Improvement on that of Pascal or an original invention, is described in the first volume of tho Misters!. lanea Berolinensia; and is still preserved in the museum at Gottingen.