Predicable (Lat. praedicabilis, that which may be stated or affirmed, sometimes called quinque voces or five words) is, in scholastic logic, a term applied to a classification of the possible relations in which a predicate may stand to its subject. It is not to be confused with 'praedicamenta', the scholastics' term for Aristotle's ten Categories. The list given by the scholastics and generally adopted by modern logicians is based on development of the original fourfold classification given by Aristotle (Topics, a iv. 101 b 17-25): definition (horos), genus (genos), property (idion), and accident (sumbebekos). The scholastic classification, obtained from Boethius's Latin version of Porphyry's Isagoge, modified Aristotle's by substituting species (eidos) and difference (diaphora) for definition. Both classifications are of universals, concepts or general terms, proper names of course being excluded. There is, however, a radical difference between the two systems. The standpoint of the Aristotelian classification is the predication of one universal concerning another. The Porphyrian, by introducing species, deals with the predication of universals concerning individuals (for species is necessarily predicated of the individual), and thus created difficulties from which the Aristotelian is free (see below). The Aristotelian treatment considered: The definition of anything is the statement of its essence (Arist. τὸ τί ἦν εἶναι), i.e., that which makes it what it is: e.g., a triangle is a three-sided rectilinear figure. Genus is that part of the essence which is also predicable of other things different from them in kind. A triangle is a rectilinear figure; i.e., in fixing the genus of a thing, we subsume it under a higher universal, of which it is a species. A property is an attribute which is common to all the members of a class, but is not part of its essence (i.e., need not be given in its definition). The fact that the interior angles of all triangles are equal to two right angles is not part of the definition but is universally true. An accident is an attribute that may or may not belong to a subject. A triangle may have "accidentally" one right angle but this not a mandatory feature for it. Differentia is that part of the essence that distinguishes one species from another. As compared with quadrilaterals, hexagons, and so on, all of which are rectilinear figures, a triangle is differentiated as having three sides. Ignoring differences, species are seen as a genus, e.g. triangles are