§5. Return to the Ground of Definition [15–16]

it is necessary that we understand how this conceptuality holds the aforementioned aspects together, where they genuinely belong; where basic experience, claim, and tendency toward intelligibility are indigenous. We will have to seek out the indigenous character of conceptuality—for we want to understand not just any basic concepts, but Aristotle’s. We will have to consult the way that Greek conceptuality and its indigenous character look. Only then can we securely pursue the scientific explication as Aristotle conducted it.13

§5. Return to the Ground of Definition

By going back to what definition originally was, we might also learn what it originally was that one today designates as concept.

a) The Predicables

Genus and species are characteristics that determine every definition. However, they are not the only determining factors. These factors include the further moment of proprium and of differentia specifica as such. These aspects, which guide concept-formation, are called predicables or κατηγορήματα. These κατηγορήματα were systematically treated for the first time by Porphyry in his introduction to Aristotle’s Κατηγορίαι. This Εἰσαγωγή was then translated into Latin by Boethius and became the basic text on logical questions in the Middle Ages. The so-called controversy over universals of the Middle Ages developed in connection with this Εἰσαγωγή. There are five predicables:

1. Genus est unum, quod de pluribus specie differentibus in eo quod quid est praedicatur. “Curved, closed line”—the genus of the circle—is predicated of many things that are distinct in species (ellipse). Still, the predicate captures what the circle in itself is.

2. Species est unum, quod de pluribus solo numero differentibus in eo quod quid est praedicatur. The individual circle solo numero differunt.

3. Differentia specifica aut διαφορά est unum, quod de pluribus praedicatur in quale essentiale, “with respect to that which belongs to what they are,” such as the rationality of the human being.

4. Proprium est unum, quod de pluribus praedicatur in quale necessarium, a “necessary” determination that belongs to the thing, but also lies outside of the essential context of genus and species.

5. Accidens est unum, quod de pluribus praedicatur in quale contingens, insofar as that which is addressed is “haphazard” (συμβεβηκός).14

These praedicabilia are also called universalia. The precise distinction consists

13. See Hs. p. 337 ff.

14. Cf. Porphyrii Introductio in Aristotelis Categorias a Boethio translata. In: Commentaria In Aristotelem Graeca. Editum consilio et auctoritate Academiae Litterarum Regiae Borussicae. Voluminis IV pars I. Berlin 1887. pp. 23–51, here pp. 26–39.

Martin Heidegger (GA 18) Basic Concepts of Aristotelian Philosophy