throne of Spain, in opposition to the grandson of Louis, and setting
forth the injurious consequences of the policy of the French monarch,
was hailed by his contemporaries as a masterpiece of historical
learning and political wisdom. By his powerful advocacy of the cause
of the Elector of Brandenburg he may be said to have aided the birth
of the kingdom of Prussia, whose existence dates with the
commencement of the last century. In the service of that kingdom he
wrote and published important state-papers; among them, one relating
to a point of contested right to which recent events have given
fresh significance: "Traite: Sommaire du Droit de Frederic I. Roi de
Prusse a la Souverainete de Neufchatel et de Vallengin en Suisse."

In Vienna, as at Berlin, the services of Leibnitz were subsidized by
the State. By the Peace of Utrecht, the house of Habsburg had been
defeated in its claims to the Spanish throne, and the foreign and
internal affairs of the Austrian government were involved in many
perplexities, which, it was hoped, the philosopher's counsel might
help to untangle. He was often present at the private meetings of
the cabinet, and received from the Emperor the honorable distinction
of Kaiserlicher Hofrath, in addition to that, which had previously
been awarded to him, of Baron of the Empire. The highest post in the
gift of government was open to him, on condition of renouncing his
Protestant faith, which, notwithstanding his tolerant feeling toward
the Roman Church, and the splendid compensations which awaited such
a convertite, he could never be prevailed upon to do.

A natural, but very remarkable consequence of this manifold activity
and lifelong absorption in public affairs was the failure of so
great a thinker to produce a single systematic and elaborate work
containing a complete and detailed exposition of his philosophical,