Originally published in Mind, 58 (1949); 59 (1950). "Author's Note" added to the reprint in Perceiving, Sensing, and Knowing, ed. Robert J. Swartz (Anchor, 1965).

Author's Note

During the past fifty or sixty years the traditional concept of sense-datum, which has been referred to, frequently because of epistemological or ontological considerations by many other names ("impression", "idea", "quale", "image", "sensum", "phenomenon", etc.) has been subjected to a type of phenomenological criticism which seems to threaten the foundations of a number of contemporary philosophical systems. Considering the fact that this criticism has been ably developed, and formulated by such distinguished men as William James, Edmund Husserl, John Dewey, and the leading psychologists of the Gestalt School, it is rather surprising to discover how much of the current literature on epistemological problems is entirely unaffected by it. Such lack of concern with vital phenomenological issues may be merely a reflexion of ignorance on the part of epistemologists, but it is probably better construed as a manifestation of the widespread belief that epistemological problems, if they are truly epistemological, not only can but should be stated and solved in abstraction from all issues which might be classified as "psychological".

Although this lack of interest in the phenomenology of perception seems to be quite widespread among philosophers, there is a small but respectable group of epistemologists who have taken a very different stand. They have maintained, in effect, that the traditional epistemological and ontological distinctions between sense-data and physical objects have been so completely annihilated by the criticism of James, Husserl, Dewey, the Gestalt Psychologists, and others, that most of the epistemology of the last three centuries is now entirely outdated. Some of them have asserted, as I shall show later, that it is no longer possible even to believe that there are any sense- data in the traditional meaning of the term; others have said, perhaps more conservatively, that although sense-data do indeed exist, it is no longer possible to distinguish their epistemological status from that of physical objects. Despite such important differences of opinion concerning the precise implications of the new phenomenology of perception, however, epistemologists who belong to this second school of thought are in complete agreement that these implications (whatever they may be) are of revolutionary importance for theory of knowledge.

It may be presumptuous to attempt to reconcile two schools of thought which have existed side by side for so many years and which have so long resisted the various forces which might have been expected to increase mutual understanding and appreciation. But the attempt is surely worth the effort, and there are grounds for believing that the differences are to a large extent the result of terminological confusions. On the one hand the critics of the traditional concept of sense-datum have frequently expressed themselves in an esoteric vocabulary which is either quite misleading or quite incomprehensible to the epistemologists. Many of the latter, on the other hand, firmly convinced that the traditional phenomenology of perception is completely adequate for the formulation and solution of philosophical problems, have not taken the trouble to seek for truth in statements of their critics which they correctly recognise to be either meaningless or absurd when interpreted in terms of the traditional vocabulary of epistemology.

In view of the nature of these obstacles to mutual understanding, I shall undertake two tasks in this paper. I shall attempt in the first part to state as clearly as possible the phenomenological theory of perception which has served as a basis for most of the recent criticism of the traditional concept of sense-datum. I shall refer to this theory as the "Percept Theory of Perception" to distinguish it from the traditional "Sense-datum Theory", and I shall limit my description of it to what I take to be the bare essentials that distinguish it from the Sense-datum Theory. To overcome the linguistic obstacles I shall make an effort to describe the Percept Theory in terms of the concepts and vocabularies of contemporary epistemologists who do not accept it, and I shall similarly illustrate the theory, when possible, by examples drawn from the writings of these same epistemologists. I shall then attempt, in the second part of this paper, to evaluate the claims of some of the philosophers who believe that the Percept Theory is of revolutionary importance for epistemology.1

Contents -- Next


1 Much of Part I and several sections of Part II are based upon the author's doctoral dissertation, Harvard University Library.

Contents -- Next