Analogy

Analogy, an-al′o-ji, n. an agreement or correspondence in certain respects between things otherwise different—a resemblance of relations, as in the phrase, 'Knowledge is to the mind what light is to the eye:' relation in general: likeness: (geom.) proportion or the equality of ratios: (gram.) the correspondence of a word or phrase with the genius of a language, as learned from the manner in which its words and phrases are ordinarily formed: similarity of derivative or inflectional processes.—adjs. Analog′ical, Anal′ogic.—adv. Analog′ically.—v.t. Anal′ogise, to explain or consider by analogy:—pr.p. anal′ogīsing; pa.p. anal′ogīsed.—ns. Anal′ogism (obs.), investigation by analogy: argument from cause to effect; Anal′ogist, one who adheres to analogy; Anal′ogon = analogue.—adj. Anal′ogous, having analogy: bearing some correspondence with or resemblance to: similar in certain circumstances or relations (with to).—adv. Anal′ogously.—ns. Anal′ogousness; An′alogue, a word or body bearing analogy to, or resembling, another: (biol.) a term used to denote physiological, independent of morphological resemblance.—Organs are analogous to one another, or are analogues, when they perform the same function, though they may be altogether different in structure; as the wings of a bird and the wings of an insect. Again, organs are homologous, or homologues, when they are constructed on the same plan, undergo a similar development, and bear the same relative position, and this independent of either form or function. Thus the arms of a man and the wings of a bird are homologues of one another, while the wing of a bird and the wing of a bat are both analogous and homologous. [Gr. ana, according to, and logos, ratio.]