Gottfried Wilhelm Leibnitz

From The Science of Language (1891) by Max Müller

... 'If Leibniz had found time to work out all the plans which his fertile and comprehensive genius conceived, or if he had been understood and supported by contemporary scholars, the science of language, as one of the inductive sciences, might have been established a century earlier. But a man like Leibniz, who was equally distinguished as a scholar, a theologian, a lawyer, an historian, and a mathematician, could only throw out hints as to how language ought to be studied. Leibniz was not only the discoverer of the differential calculus. He was one of the first to watch the geological stratification of the earth. He was engaged in constructing a calculating machine, the idea of which he first conceived as a boy. He drew up an elaborate plan of an expedition to Egypt, which he submitted to Louis XIV in order to avert his attention from the frontiers of Germany. The same man was engaged in a long correspondence with Bossuet to bring about a reconciliation between Protestants and Romanists ; and he endeavoured, in his Théodicée and other works, to defend the cause of truth and religion against the inroads of the materialistic philosophy of England nd France.'   ...

Founded on lectures delivered at the Royal Institution in 1861 and 1863
New York : Scribner's Sons 1891, vol. i, pp. 152-153.

From What Is Meaning? (1903) by Lady V. Welby

'Like Bruno, Leibnitz hoped for a science of signs, an algebra of thought, but he aimed at a system in which to reason and to calculate were identical, reason being literally ratio.   (Etc.)

Per Classics in Semantics
Editors Hayden and Alworth
New York : Philosophical Library 1965, note on p. 214.

From On Determinism, 1922 (rev. Nov. 1946) by Jan Łukasiewicz

I belong, with a few fellow workers, to a still tiny group of philosophers and mathematicians who have chosen mathematical logic as the subject or the basis of their investigations. This discipline was initiated by Leibniz, the great mathematician and philosopher, but his efforts had fallen into oblivion when, about the middle of the nineteenth century, George Boole became its second founder. Gottlob Frege in Germany, Charles Peirce in the United States and Bertrand Russell in England have been the most prominent representatives of mathematical logic in our own times.

POLISH LOGIC 1920-1939
editor Storrs McCall
Oxford 1967, pages 19-20.

From Mathematics, 1923 by David Eugene Smith

Modern Calculating Machines.   It is evident that the idea of our modern calculating machine finds its root in the Greek abacus. When Pascal (1642), seeking to save himself unnecessary labor in assisting his father make up his accounts, invented the first modern adding machine, he simply made a set of wheels which were geared in such a way that that figure 1 would be carried when ten appeared in units' place. In other words, he invented a machine that would do automatically what had been done by hand on the Greek abacus. Leibniz (1673) added to this a further device that permitted of multiplication as well as addition, and from that time to the present adaptations of the idea of the abacus have continued and improved until we now have numerous types of instruments for all the kinds of numerical calculation ; all of these, however, go back to the abacus.

Boston, Massachusetts : Marshall Jones 1923, pp. 105-6.

Selected bibliographic

Author Leibniz, Gottfried Wilhelm, Freiherr von, 1646-1716. Title(s) Hauptschriften zur grundlegung der Philosophie. Übersetzt von A. Buchenau. Durchgesehen und mit Einleitungen und Erläuterungen hrsg. von Ernst Cassirer. Edition (3., mit Literaturhinweisen ergänzte Aufl.) Publisher Hamburg, Meiner (1966) Paging 2 v. plate. 19 cm. Series Philosophische Bibliothek ; Bd. 107-108 Notes Previous editions published as part of author's Philosophische Werke. Bibliography: v. 2, p. [580]-584.