Section 1

Phenomenologists think they can explain how empirical knowledge is possible. Like Kant, they think that inner experience is possible only if outer experience is possible. To borrow Sartre’s famous slogan: consciousness is always consciousness of something. They proceed to explain how outer experience is possible by trying to answer the question: how is it possible for experience to be intentionally directed at something? Having explained how outer experience is possible they take themselves to have accounted for the possibility of empirical knowledge.

Section 2

Phenomenologists attack naturalism for presupposing the possibility of empirical knowledge. They think that the only way to explain the possibility of knowledge is by identifying the set of a priori conditions in virtue of which a state is intentionally directed at the world.

Naturalists, for there part, would attack phenomenologists by arguing that there is no external vantage point, outside of knowledge, from which we can identify the conditions that make knowledge possible. It makes no sense to suppose that there is such a vantage point from which we can pose the phenomenologist’s question.

Naturalists could agree that what is needed to explain the possibility of empirical knowledge is an explanation of how experiences can be intentionally directed at the world. They think we can answer this question by specifying, in non-intentional terms, the conditions under which some state can count as a representation. Intentionality is a perfectly natural feature of the world; there is no need to appeal to anything outside nature - anything transcendental or non-empirical - to account for intentionality.

Section 3

Phenomenologists would counter that the naturalist philosopher continues to presuppose what needs to be explained. To try to identify a set of naturalistically specifiable conditions definitive of intentionality is to presuppose that we can have knowledge of nature. For, we can only identify which natural conditions explain intentionality, if we assume that our knowledge of nature is unproblematic. Yet, what we were looking to explain is how knowledge is possible.

However the phenomenologist remains vulnerable to the objection that no sense can be made of the non-empirical or transcendental standpoint we are asked to take up if we are to account for knowledge. For I shall argue (following Barry Stroud) that the only way to make sense of a non-empirical, transcendental form of philosophy is to presuppose transcendental idealism. Unfortunately, the only way to make sense of transcendental idealism is in terms of such a transcendental or non-empirical form of inquiry. Thus, the transcendental philosopher seems to be caught in a tight circle.

Section 4

We have arrived at our antinomy. I assume that all parties accept it is possible to know about the empirical world. Either we take knowing to be a perfectly natural phenomena and set about specifying the conditions a creature must satisfy if it is to have knowledge. This, according to phenomenologists, requires us to presuppose what we want to explain¾knowledge. So we wind up having given no account of how knowledge is possible.

Alternatively, we can attempt to identify, through a priori reflection, the conditions that an experience must satisfy if it is to be intentionally directed at the world. This strategy requires us to make sense of a kind of non-empirical or a priori style of inquiry. There does not seem to be any non-circular account to be had of what such a form of inquiry consists in.

Neither phenomenology nor naturalism seem to be able to supply a satisfactory answer to the question: how is knowledge possible? Both require us to presuppose something. Naturalism presupposes what we need to explain: the possibility of knowledge. Phenomenology must presuppose the truth of idealism. Must we conclude that any attempt to show how knowledge is possible cannot succeed?