LAPLACE, PIERRE-SINION. A life of Laplace can hold no middle place between a short account for the general reader, and a detailed description of his labours for the reference of those who read his works. Independently of the Later being too long for this work, we have a specific reason for avoiding it, which will appear in the course of this article: namely, that the writings of Laplace do not give specific information as to what was done by himself and what by others; and that no ono has yet supplied the deficiency.
Pierre-Simon Laplace was born March 1749, at 13enumont-en-Auge, near Honfleur, and was the son of a farmer. He received a good education, and appears at first to have turned his attention to theology ; but as early as the age of eighteen he went to Paris, having previously taught mathematics at his native place. He had letters of intro duction to D'Alembert, but finding that they procured him no n4ice from that philosopher, he wrote him a letter on some elementary points of mechanics, with which D'Alembert was so much pleased that ho sent for Laplace the same day, telling him that he bad found a better way of calling attention to his claims than by letters of introduction. Shortly afterwards, in 1763 or 1769, the recommenda tion of D'Alembert procured for Laplace a chair of mathematics at the military school of Paris. In 1772 Laplace showed his powers in a paper on integration of equations of finite differences in the ' Memoirs of the Academy of Turin ; ' and from that time his scientific life was one achievement after another, until he attained a reputation almost Newtonian with the world at largo, and of the highest extent and character among mathematicians, who, though they cannot even compare walks of so different a kind as those of Newton and Laplace, feel that the latter must be named next after Lagrange, and the two together above all the followers of the first.
The political life of Laplace was not so favourably distinguished. In 1799 the First Consul made him minister of the interior. With the views which Napoleon always professed with respect to science, it is not wonderful that he should have made the experiment of trying to strengthen his administration by the assistance of a philosopher whose rising fames made the French expect to claim a name which should rival that of Newton. But the experiment was not successful;
and after a very short period the First Consul removed Laplace to the head of the Benet conservateur. The subsequent account given by Napoleon of his minister will be a part of the biography of Laplaco in all time to come. "A mathematician of the highest rank, he lost not a moment in .showing himself below mediocrity as a minister. In his very first attempt at business the consuls saw that they had made a mistake. Laplace looked at no question in its true point of view. He was always searching after subtleties; all his ideas were problems, and he carried the spirit of the infinitesimal calculus into the management of business." This pointed satire is not, we suspect, one of which the force will be always admitted; first, because it in so very like what a satirist ought to say of a mathematician ; secondly, because the character of Laplace's mathematical writings is signally and ridiculously the opposite of all the preceding, as wo shall presently notice. That Laplace was an incompetent minister is probable ; but this is not the worst.
In 1814 he voted for the deposition of his benefactor, a step which might have been justifiable on public grounds : but nothing can excuse tho suppression of the dedication to Napoleon, which stood at the front of Lin Th6orie, des Probabilitee during the prosperity of his benefactor, and no longer. Laplace, who had been created a count by Napoleon, and a marquis by Louis XVIII. immediately after the restoration, did not appear at court during the short restoration of the former. Of his political conduct during the revolution wo have no account, except that he was at one time under the auepicion of the authorities, and was removed from the commission of weights and measures. In the suppression of the dedication, which we now cite entire, and which appeared In 1812, end not in 1814, there is a prima facie appearance of ingratitude and pusillanimity, the evidence of which, if not answered, should be perpetuated.