NEW CATEGORIES for FORMAL ONTOLOGY Peter SIMONS

NEW CATEGORIES FOR FORMAL ONTOLOGY

Peter SIMONS Universität Salzburg

What is at first small is often extremely large in the end. And so it happens that whoever deviates only a little from truth in the begin• ning is led farther and farther afield in the sequel, and to errors that are a thousand times larger. Pranz Brentano, On the Several Senses of Being in Aristotle, p. 1.

1. The Several Sources of Categories

One of the more instructive characteristics of Jaakko Hintikka's philosophy is the way in which he uses modern methods and results to throw light on classical philosophical themes. One which is of particular interest for an ontologist is his account of categories. I Hintikka's investigations, as he is well aware, have many historical precedents. When Aristotle elaborated his kategoriai it was in terms both of most general words (predicaments, as the medievals called them), that can be said of individual things, and also as different basic kinds of things, corresponding to different ways in which something may be said to be or exist. 2 Several of Aristotle's cate• gories are given using question-words functioning like the English

1. See Hintikka 1983, eh. 8, Hintikka 1986. As will be evident to those even casually acquainted with the many philosophical concems of Jaakko Hintikka, this essay crosses his tracks in several places apart from that of categories. for example in issues of free logic, modality, analyticity, and history of philosophy. I intend to take up some of these issues at greater length elsewhere. 2. The idea of categories as predicaments can be found in the book Categories, the idea of categories as ways something can be said to be in the Topics and Metaphysics. 78 where and when. Averroes and, following hirn, Ockham, drew a close connection between the categories and the kinds of things we can ask using basic question-words, often those that begin with qu• in Latin, wh- in English, or w- in German. The idea that Aristotle's categories are directly motivated by linguistic distinctions in his native Greek was propounded by Adolf Trendelenburg in the 19th Century and Emile Benveniste in the 20th, and later commented upon at length by Charles Kahn. 3 Despite the prima facie linguistic starting-point for the categories however, it does not thereby follow that categories reflect merely linguistic distinctions. Maybe lan• guage is providing here, for reasons to be discovered, a reliable guide to at least some of the fundamental kinds of entity. The paucity of Aristotelian justification for the choice and nature of the categories did not make it easy for the interpreters. Are categories just word-classes, or do they correspond in all human languages to the same concepts in terms of which we perforce conceptualize reality, or do they divide reality at the joints? When• ever the Aristotelian categories were taken seriously, at least one of these answers was espoused, and sometimes more than one at once. Some commentators held that categories are all three: word• classes, concepts we perforce think by, and fundamental classes of entity. Wh at was lacking from such assumptions of harmony be• tween language, thought and the world was a convincing account of how such harmony came about. The same question indeed arises for any system of categories, notjust the Aristotelian: why just these, no more and no less, and no others? Kant provided one possible ans wer for his categories. They are the concepts we must use whenever we think about the world at all. For this reason, Kant thought there was no way past them to an account of the world as it is in itself as distinct from the world as it appears to and is structured in thought by uso But whatever the role of concepts and other subtler structures of awareness and thought, it is not warranted to suppose we are forever cut off from an investigation of the world as it is in itself. Considering categories from the position Hintikka adopts, namely one where we look at the basic kinds of questions which a particular

3. Trendelenburg 1846, Benveniste 1964, Kahn 1973, 1978.