COMPARISON is the act of carrying the mind from one object to another, in order to discover some relation subsisting between them. The result of comparison is knowledge, which the intellect apprehends, but the act is an exercise of attention voluntarily directing the energy of the mind to a class of objects or ideas, and attended by judgment. The result of comparison is a judgment. Comparison may thus be regarded as the essential act of thought in all its forms, more simple as well as more complex. The concept, e.g., is the result of the comparison of individual phenomena, the judgment of that of concepts, and the inference of that of judgments. The theorems of mathematics, e.g., are a series of judgments arrived at by comparison, or viewing different quantities and numbers in their relations.
