SOURCE: "On Leibniz's Metaphysics," translated by R. Allison Ryan, in Leibniz: A Collection of Critical Essays, edited by Harry G. Frankfurt, Anchor Books, 1972, pp. 19-45.

In the essay below, originally published in French in 1902, Couturat argues the importance of logic and reason in Leibniz's philosophy.

In the preface to La Logique de Leibniz, we asserted that Leibniz's metaphysics rests entirely on his logic. This thesis is confirmed implicitly in our book and is evident from the texts we had occasion to cite there. Nevertheless, since it is contrary to the classical interpretations and to current opinion, it will be useful to establish it explicitly and in detail. Moreover, although it appears to us to be sufficiently proven by the texts which are already known, we are now able to confirm it by adducing some unpublished documents of unusual value and importance. The most interesting and most significant is...