Franz Brentano (essay date 1862)
SOURCE: "Potential and Actual Being," in On the Several Senses of Being in Aristotle, by Franz Brentano, edited by Rolf George, translated by Rolf George, University of California Press, 1975, pp. 27-48.
[In the following essay, originally published in 1862, Brentano discusses the nature of potential and actual being as analyzed by Aristotle in Metaphysics. Brentano examines Aristotle's definitions of potential and actual being and presents readings of them designed to resolve some difficulties within them. Finally, he explores the relationship between the two concepts, maintaining that "movement is the actuality of the potentiality."]
The two senses of being …, namely, being which is divided into the categories and potential and actual being, belong together and are intimately connected with each other.1 Thus they have in common that the science of being, metaphysics, is concerned in the same way with one as with the other,2 while, as we saw, both accidental being and being in the sense of being true were excluded from it. Since being, as the most general, is asserted of everything,3 it follows for the subject of metaphysics that it comprises everything insofar as it has extramental being which is one with it and belongs to it essentially. Hence it follows that, just as the being which divides into the categories, being in the sense now under discussion is being that is independent and outside the mind [on kath' hauto exo tes dianoias].
l. The kind of being which is divided into actual [on energeia] and potential [on dynamei] is being in the sense in which this name is applied not only to that which is realized, that which exists, the really-being, but also to the mere real possibility of being.
Potential being [on dynamei] plays a large role in the philosophy of Aristotle, as does the concept of matter [hyle]. Indeed, these two concepts are coextensive,4 while actual being [on energeia] is either pure form or is actualized by form.
There is a great difference between what we here mean by the potential [the dynaton or dynamei on] and what in more recent times is meant by calling something possible in contrast with real, where the necessary is added as a third thing. This is a possibility which completely abstracts from the reality of that which is called possible, and merely claims that something could exist if its existence did not involve a contradiction. It does not exist in things but in the objective concepts and combinations of concepts of the thinking mind; it is a merely rational thing.
Aristotle was quite familiar with the concept of possibility so understood, as we can see from De interpretatione, but it bears no relation to what he calls potential being, since otherwise it would have to be excluded from the subject of metaphysics along with being as being true. So that no doubt may remain, he mentions in Met. [Metaphysics] V. 12, as well as in IX. 1, the impossible whose contrary is necessarily true [adynaton hou to enantion ex anankes alethes] (Met. V. 12. 1019b23). The possible object [dynaton] which is associated with this impossibility is distinguished from the potential object [dynaton] which bears this name because it stands in relation to a power [dynamis]. It is the same only in name5 and must be distinguished from this potentiality along with the powers of mathematics, a2, b3, etc., which are powers only in a metaphorical sense [kata metaphoran].6 Thus he speaks here of something which really has potential being. This is based upon his peculiar view that a non-real, something which has, properly speaking, non-being (me on)7, in a manner or speaking exists insofar as it is potentially, and it is this which leads him to a special wide sense of real being, which comprises as well that which potentially is.
Now, what is this potential thing which, being real, belongs to the object of metaphysics, and which has potential being as opposed to actual being? Aristotle defines it in the third chapter of the...
(The entire section is 51,243 words.)