GEORGE BOOLE (1815-1864), English logician and mathematician, was born in Lincoln on the 2nd of November 1815.
It is the business of the logician to find the causes of the judgments which form the premises and the conclusions of inference, reasoning and science.
The System der Logik (1828) of Bachmann (a Kantian logician of distinction) contains a historical survey (pp. 569-644), as does the Denklehre (1822) of van Calker (allied in thought to Fries), pp. 12 sqq.; Eberstein's Geschichte der Logik and Metaphysik bei den Deutschen von Leibniz bis auf gegenwartige Zeit (latest edition, 1 799) is still of importance in regard to logicians of the school of Wolff and the origines of Kant's logical thought.
It was because the aftermath of Newtonian science was so rich that the scientific faith of naturalism was able to retain a place besides its epistemological creed that a logician of the school could arise whose spirit was in some sort Baconian, but who, unlike Bacon, had entered the modern world, and faced the problems stated for it by Hume and by Newton.
He gradually became a logician out of his previous studies: out of metaphysics, for with him being is always the basis of thinking, and common principles, such as that of contradiction, are axioms of things before axioms of thought, while categories are primarily things signified by names; out of the mathematics of the Pythagoreans and the Platonists, which taught him the nature of demonstration; out of the physics, of which he imbibed the first draughts from his father, which taught him induction from sense and the modification of strict demonstration to suit facts; out of the dialectic between man and man which provided him with beautiful examples of inference in the Socratic dialogues of Xenophon and Plato; out of the rhetoric addressed to large audiences, which with dialectic called his attention to probable inferences; out of the grammar taught with rhetoric and poetics which led him to the logic of the proposition.
It is nearer to Plato's analysis of the sentence, and no logician would have gone back to it, after the Prior Analytics.
He was a prolific writer, and at the time of his death he occupied the foremost position in England both as a logician and as an economist.
It is clear then that a man's metaphysics and psychology must colour his logic. It is accordingly necessary to the logician to know beforehand the general distinctions and principles of things in metaphysics, and the mental operations of sense, conception, memory and experience in psychology, so as to discover the processes of inference from experience about things in logic.
As a logician Lotze stands among the masters.
Gilbert is almost the only logician of the 12th century who is quoted by the greater scholastics of the succeeding age.