interest, but an addition to human knowledge as complete in itself, as permanent, and as irrefragable, as the Geometry of Euclid. It is true that Aristotle did not cover and exhaust the entire field in reasoning, just as Euclid did not exhaust the theory of all the properties of space. But so far as he went Aristotle was perfect. His work took its origin out of the examination of dialectical controversies, which, at the time when he wrote, much predominated over all that we should think worthy of the name of physical science, and therefore his aim was limited to the analysis of deductive reasonings. But men still reason deductively, and will always do so; during a great part of life we are employed, not in finding out new laws of nature, but in applying what we knew before, in appealing to general beliefs, or supposed classes of facts, and in drawing our positive or negative conclusions accordingly. To all this process, whenever it occurs, the ‘Analytics’ of Aristotle are as applicable as the principles of Geometry are to every fresh mensuration.
Aristotle invented the word “Syllogism,” for the process of putting two assertions together and out of them deducing a third. This word indeed existed before in Greek literature, but in a general sense, meaning “computation,” “reckoning” or “consideration.” But Aristotle stamped it with the technical meaning which it has ever since borne. In introducing the word, however, it must not be supposed that he introduced, or invented, the process of reasoning to which he applied it, or that he ever pretended to do
