PERCEPTION

(Lat.) In Mental Philosophy, that power, act, or state of the mind, which has a conscious reference to external objects. Various theories of perception have arisen among philosophers, differing as this reference is supposed to be more or le immediate, or as the objects to which it refers are conceived to po e an independent reality or not. These theories are designated by the terms idealism and realism j which latter is subdivided into natural or positive, and relative or negative realism. The best known system of idealism is that of Bishop Berkeley. See Idealism. According to the scheme of negative or relative realism, all that we can know of an object is the feeling which it excites in our minds. The cause of this feeling we nece arily judge to be something external to ourselves; but what it is in itself we have no means of knowing. This is the view adopted by the great majority of philosophers, from Plato and Aristotle down to Kant and Brown. The theory of natural realism is the one supported by Dr. Reid under the name of the comtnon-sense system. This philosopher conceives the object in perception to be in some way ivitnediatelp present to our consciousne ; its qualities are not merely felt by us, but discovered in it. We derive a certain sensation from the whitene or roundne of an object; but it is the object itself and not our minds that are white or round. This doctrine, which was also that of the ancient Stoics, and expre ed by them in nearly the same words as those used by Reid (see Cicero, Acad. Qucest.), is in fact rather a statement than an explanation of the problem. It has 911 PERFECT NUMBER. been recently supported with great acutene by a learned writer in the Edin. Review, No. 1 13.; to which we refer our readers for a full account of all po ible theories of perception. PERCH, in Land Measure, is the fortieth part of a rood, or equal to 30i square yards. Perch is also sometimes used as a denomination of long measure, when it signifies the same thing as a rod or pole, being bl yards, or IGi feet. [s. 924]