There,' says he, 'I took my doctor's degree in my twenty-second year, maximo omnium applausu; for when I maintained my public thesis, Í discoursed with so much facility, and explained myself with so much clearness, that not the auditors only wondered at this new and unusual xpißux, specially in a lawyer, but even those who had engaged to respond, publicly acknowledged that I had excellently well satisfied them.' Refusing an offer of a Professorship at Altdorf, Leibnitz repaired to Nuremburg. While there, he happened to hear of a Society of Alchemists, who were prosecuting, with the usual success, the search after the 'philosopher's stone.' He was seized with a strong desire to become acquainted with these adepts; but, as he was absolutely ignorant of all their terms of art, he knew not how to negotiate an introduction. Happily he recollected that their ignorance must be quite equal to his own; and so, boldly extracting frem the writings of the most celebrated Alchemists, all the most obscure terms he could find, he composed .a letter, of which he did not understand a syllable; and from that moment became, if one may indulge in the paradox, as knowing as themselves. What was dark to himself was happily quite clear to these illuminati, who, following their usual instinct for nonsense, or afraid to be supposed ignorant, professed to augur favourably of one who could write so profoundly. They invited him to assist at their conferences, introduced him to their laboratory, and made him their secretary.

While at Nuremburg, he met with a valuable friend and patron in the Baron de Boineburg, Chancellor of the Elector of Mentz. Chance (some say) brought them together at the hotel where Leibnitz was lodging. The Baron, who, amidst his official duties, had never ceased to cultivate science and literature, was struck with the talents and attainments of his young acquaintance. He gave him his counsel,-advised him to attach himself to Jurisprudence and History, as the studies which would furnish him with the best means of advancing himself in life, and exhorted him to repair to Frankfort-on-the-Maine for the further prosecution of those studies: meantime, he promised to endeavour to procure for him some office worthy of his talents in the Court of the Elector. With this advice Leibnitz complied, and at Frankfort abandoned himself entirely to the studies thus recommended. It was there, amidst many distractions, that he composed, in 1667, his little treatise entitled, 'A New Method of Learning and Teaching Jurisprudence.' This early work displays all his principal characteristics-his vast reading, the acute

* Nova Methodus discendæ docendæque Jurisprudentiæ,

ness, originality, and comprehensiveness of his mind, and his propensity to form projects too vast for fulfilment, and to make promises which sound something like presumption. This little treatise was in the press when the Baron de Boineburg summoned him to the service of the Elector of Mentz; and the young author, with the new-developed instinct of a courtier, dedicated his work to his patron. In 1668, he followed up his Nova Methodus, by his Ratio Corporis Juris reconcinnandi,-a beautiful project,' as M. Jaucourt calls it—' un beau projet'-nothing less in fact than a new digest of Universal Law.

But the author we have just cited might well ask, can we believe that Leibnitz (then little more than twenty-two years of age) had sufficient light for a reform of this gigantic kind?' A faire un bon livre, as M. Jaucourt says, is all that could be expected of the splendid talents of any young philosophereven of a Leibnitz-engaged on such a subject.

In the same year, he also published his treatise De Arte Combinatoriâ; in which, though he advances many things which he afterwards saw cause to reject, he displays much of the analytical skill, and originality of conception, which afterwards made him so famous in the field of pure mathematics. The abdication of John Casimir, King of Poland, in 1668, when the elective throne was besieged by a crowd of aspirants, afforded Leibnitz his first opportunity of signalizing his talents in political discussion. Amongst the claimants was the Prince of Neuburg, and Boineburg engaged Leibnitz to support his pretensions. In this, as in one or two other cases, our author was perhaps too easily led to accept the office of advocate, before exercising that of philosopher; to accept a thesis and then examine how it could be supported. Once engaged, however, his philosophic habits of mind soon appear in this as in similar instances; and, rising above the transitory and limited subjects proposed, he expatiates on the condition of Poland, its principles of government, and the qualities it should seek in the monarchs of its choice. Though this brochure did not attain its end, Leibnitz was not without his reward. At the instigation of Boineburg he was made a member of the Council of the Elector, a post which he held till 1672. Without neglecting its duties, his ever active mind found time to produce numberless pieces on the most diversified subjects, which secured him extensive reputation, but which it is beyond our limits even to enumerate. One of his greatest projects at this period, but, like many others, never executed, was to revise and remodel the Encyclopædia of Alstedius, according to a new method, founded on the relations of the various sciences to each other. A curious publication, which appeared in 1670, was very

characteristic of his literary habits. He had long been of opinion that Aristotle had been depreciated below his real merits, in the necessary recoil against the tyranny of the Scholastic Philosophy. Instead of treating this subject systematically, in the shape of a distinct dissertation, he contents himself with republishing a work against Aristotle, written by Mario Nizoli, a native of Modena, so early as 1553, to which our author adds a letter to Thomasius, a preface, and notes!

At

In 1672, Leibnitz went on a political mission to Paris, where he spent a considerable time, and in a very different way from the generality of foreign visitors of that gay metropolis. He pursued his studies with his usual intensity, but particularly applied himself to Mathematics, in which he frankly represents himself as up to that time comparatively uninitiated. Paris, in 1672, he became acquainted with Huygens; and the perusal of some of his writings, together with the study of those of Galileo and Descartes, and the Mathematical Fragments of Pascal, inspired him with a zeal in his new pursuit, which, combined with his great inventive talents, soon put him not only in possession of all that had been hitherto discovered, but prompted him to make discoveries for himself.

On the all but exhausted controversy of the Differential Calculus, and of Leibnitz's claims to be considered an inventor, we have little to say in addition to what has been already often repeated; and that little has been suggested solely by the observations which Dr Guhrauer has, in his recent biography, thought proper to make. Our remarks on his statements will

occur farther on.

Whilst prosecuting his mathematical studies, Leibnitz noted certain imperfections in the Arithmetical Machine which Pascal bad endeavoured to construct; and with his characteristic ambition of attempting all things difficult, he conceived the idea of im proving and perfecting it. To this task he devoted considerable time, thought, and money; and he has left a brief account of his success in the third volume of his works.* But he was at length obliged to abandon it; and it thus forms one of the huge pile of projects which he has left incomplete, and which serve only to show the activity and universality of his genius.

In the year 1673 Baron de Boineburg died; and as official duties no longer confined Leibnitz to Paris, he took the opportunity of visiting England, and there became acquainted with Boyle, Oldenburgh, Gregory, Wallis, Newton, and others.

* Dutens' edition, Vol. iii. p. 413.

Several of the literary and seientific acquaintances he here made, were added to the Contributors to his already vast correspondence. Shortly after his arrival in England, his patron, the Elector of Mentz, died, (1674,) and Leibnitz resolved to return to Germany, and to push his fortunes in some other direction. Previous to his leaving England, the Royal Society honoured him, and did themselves honour, by enrolling him amongst their members. As soon as he arrived in Paris, he wrote a letter to John Federic, Duke of Brunswick-Lunenburg, to inform him of his situation; and that Prince immediately offered him a place at his Court, a pension, and, what was as much prized, the liberty of remaining in foreign countries as long as he pleased. Availing himself of this permission, Leibnitz remained at Paris five months, chiefly engaged in the prosecution of his mathematical studies. He then returned for a brief interval to England, thence paid a visit to Holland, and took his place at the Court of his sovereign at Hanover, in 1676; and with this Prince and his successors he spent the remainder of his life.

The tastes of the Duke so happily coincided with those of Leibnitz, that he must have been here perfectly in his element. He commenced his duties with the agreeable task of enriching the ducal library with important works and manuscripts. His patron often joined him in his physical and chemical studies; and thus Leibnitz doubtless found it less tedious to play the Courtier, than a philosopher in that situation may be supposed apt to find it.

The Prince died in 1679, but Leibnitz lost nothing by his death; as his successor, Prince Ernest Augustus, then Bishop of Osnaburg, cherished towards him the same sentiments, and retained him in the same employments. He engaged him, however, in one new task, which, had it not been for the eccentric manner in which Leibnitz most characteristically performed it, would have involved a mere waste of time, and, as it was, must have grievously interrupted studies far more important and congenial. It was that of writing the History of the House of Brunswick. Here, as in all like cases, he broke away from the comparatively narrow limits assigned to him; and in the course of his very comprehensive researches, in which he amassed an enormous quantity of materials, (some of them very remotely connected with his proposed subject,) his active mind suggested many novel and sometimes brilliant speculations, in various branches of science; more especially in relation to Geology, (of which he may, in virtue of his Protogea, be called the founder,) comparative philology, and the whole philosophy of history and antiquities. For an ample collection of materials he travelled during the years 1687, 88, 89;-visiting Franconia,

Bavaria, Suabia, Austria, and subsequently Italy.* Libraries, monasteries, convents, abbeys, tombs, public documents, manuscripts, rare books, were all laid under contribution. On his return in 1690, he reviewed the treasures thus acquired, and was surprised to find he was so rich. In collecting materials for the history of Brunswick, his huge drag had brought up all sorts of fragments of antiquity, many of them highly curious. From these accumulations, and from the treasures in Wolfenbuttel, recently committed to his care, he selected the materials of a great work, which he calls Codex Juris Gentium Diplomaticus. It is in fact a collection of treaties, declarations, manifestoes, contracts of royal marriages, and public documents of a similar nature. It extended to two folio volumes, the first of which appeared in 1693; the second volume, enriched by communications from Oxenstiern, not till 1700. To the first volume is prefixed a preface, indicating as usual the activity and diffusiveness of his genius, his power of eliciting general truths from the most unpromising facts, and of throwing unexpected light on subjects but little connected with one another.

Another work which originated in the task imposed upon him by the Elector, consisted of his Accessiones Historica, published in 1698. It is in fact a mass of the odds and ends of his multifarious Collections; many of them rare documents, which had been buried in public libraries, and had escaped the vigilance of previous inquirers. In order to finish here all notice of the series of publications which had their origin in the request of the Elector, we may remark, that it was not till 1707, nearly twenty years after he set out on his travels, that the first portion of any work exclusively bearing on his subject saw the light; and that consisted only of a collection of the writers on the affairs of Brunswick. The second and third volumes appeared in 1710 and 1711. This extensive work was to have been succeeded by a work on the History of Brunswick itself and its Illustrious House; that is, by the work which for twenty years

* It was during these travels that a curious incident happened to him. He was once overtaken in a small vessel on the coast of Italy by a furious tempest, which the sage skipper attributed to the presence of the heretical German. Presuming him ignorant of the language, he and his crew began to deliberate on the propriety of throwing the Lutheran Jonas' (as M. Jaucourt expresses it) overboard. Leibnitz, with much presence of mind, took out a Rosary, which he happened to have with him, and began to tell his beads with vehement devotion. The ruse succeeded. † Scriptores Rerum Brunsvicensium illustrationi inservientes.