Tim Crane

Franz Brentano’s attempt to distinguish mental from physical phenomena by employing the scholastic concept of intentional inexistence is often cited as reintroducing the concept of intentionality into mainstream philosophical discussion. But Brentano’s own claims about intentional inexistence are much misunderstood. In the second half of the 20th century, analytical philosophers in particular have misread Brentano’s views in misleading ways.1 It is important to correct these misunderstandings if we are to come to a proper assessment of Brentano’s worth as a philosopher and his position in the history of philosophy. Good corrections have been made in the recent analytic literature by David Bell (1990), Dermot Moran (1996), and Barry Smith (1994) among others. But there is also another, more purely philosophical lesson to be learned from the proper understanding of Brentano’s views on this matter. This is that Brentano’s struggles with the concept of intentionality reveal a fundamental division between different ways of thinking about intentionality, an division which Brentano himself does not make fully clear. Making the nature of this division explicit is the aim of this paper

The Vienna Circle was a group of scientifically-minded philosophers, many physicists by training, who in the 1920s and 30s developed the cluster of philosophical doctrines known as Logical Positivism. Among the Circle’s most distinguished members were Rudolf Carnap and Herbert Feigl, each of whom emigrated to America during the Nazi era. It is said that Feigl, the author of an important 1958 monograph defending a materialist approach to the mind-body problem, once gave a visiting lecture on the problem of consciousness at UCLA, where Carnap was teaching. Feigl argued that although there were good reasons for believing that the mind is fundamentally physical, the physical explanation of the ‘qualia’ of sensory experience – the ineffable sensory qualities involved in, say, smelling coffee – was still a mystery to science. Now the story becomes apocryphal. Carnap is supposed to have interrupted, ‘But Feigl, there is something missing from your lecture. Science is beginning to explain qualia in terms of the alpha factor!’. We can imagine Feigl somewhat alarmed by this interjection from the great Carnap: ‘But Carnap, please tell me: what is the alpha factor?’. ‘Well, Feigl’ Carnap replied ‘if you tell me what qualia are, I’ll tell you what the alpha factor is’.

If you stare for a period of time at a scene which contains movement in one direction, and then turn your attention to an object in a scene which contains no movement, this object will appear to move in the opposite direction to that of the original movement. The effect can be easily achieved by attaching a piece of paper with a spiral drawn on it to the spinning turntable of a record player, and then turning the turntable off while continuing to look at the spiral (see Frisby 1979, pp. 100-101 for a detailed descrip- tion of how to bring this about). But the illusion of movement can also occur when looking at a waterfall, for instance, and turning one's attention away from the waterfall to a stationary object such as a stone; hence its name - the 'Waterfall Illusion'.

In an earlier paper [3], D. H. Mellor and I argued that physicalism faces a dilemma: 'physical' is either taken in very restrictive sense, in which case physicalism is clearly false; or it is taken in a very broad sense, in which case the doctrine is almost empty. The challenge to the physicalist is to define a doctrine which is both defensible and substantial. Philip Pettit [4] accepts this challenge, and responds with a definition of physicalism which he thinks avoids the dilemma. Pettit's definition of physicalism involves four claims, two about entities, two about laws. Claims 1 and 3, concerning the existence of microphysical entities and microphysical laws, should not be questioned. Claims 2 and 4 are what make Pettit's theory physicalist: 2 says that microphysical entities constitute everything, 4 says that microphysical laws govern everything. I shall argue that the various ways Pettit offers of understanding these claims are in tension with one another, with the result that his definition does not avoid the dilemma posed in [3].

Philosophers of mind typically conduct their discussions in terms of mental events, mental processes, mental properties, mental states – but rarely in terms of minds themselves. Sometimes this neglect is explicitly acknowledged. Donald Davidson, for example, writes that ‘there are no such things as minds, but people have mental properties, which is to say that certain psychological predicates are true of them. These properties are constantly changing, and such changes are mental events’.2 Hilary Putnam agrees, though for somewhat different reasons: The view I have long defended is that the mind is not a thing; talk of our minds is talk of world-involving capabilities that we have and activities that we engage in. As Dewey succinctly put it, “Mind is primarily a verb. It denotes all the ways in which we deal consciously and expressly with the situation in which we find ourselves. Unfortunately, an influential manner of thinking has changed modes of action into an underlying substance that performs the activities in question. It has treated mind as an independent entity which attends, purposes, cares and remembers”. But the traditional view, by treating mental states as states of the “underlying substance”, makes them properties of something “inside”, and, if one is a materialist philosopher, that means properties of our brains. So the next problem naturally seems to be: “Which neurological properties of our brains do these mental properties ‘reduce’ to?” For how could our brains have properties that aren’t neurological? And this is how materialist philosophers saw the problem until the advent of such new alternatives in the philosophy of mind and philosophy of language as Functionalism and Semantic Externalism.

The best definition of philosophy, in my opinion, was given by Wilfrid Sellars fifty years ago: ‘The aim of philosophy, abstractly formulated, is to understand how things in the broadest possible sense of the term hang together in the broadest possible sense of the term’. This definition does not get us very far; and nor should we expect it to (after all, as Nietzsche said, only that which has no history can be defined). But it does give us something to get started on. One important element in the definition, for example, is the emphasis on the ‘breadth’ of philosophy. Another is the idea of ‘hanging together’. Yet another, which I want to focus on here, is that philosophy is a form of understanding. Philosophy is a cognitive, rather than an aesthetic or a practical endeavour, aiming at an improvement in our cognitive position rather than at edification or political activism. Certainly philosophy has resulted in edification and political activism, and no doubt it will do in the future too. But this is not its aim.