The Phenomenological Negation of the Causal Closure of the Physical

The aim of this paper is to provide a phenomenological demonstration that the causal closure of the physical is false. To begin I should like to clarify the notion of the physical I have in mind. As an example, consider the experience you are having now. I am assuming your eyes are open and you are seeing something. That something, taken in the ordinary sense, is the physical world, made up of physical spaces and objects, such as tables and chairs, and physical events involving such spaces and objects. In everyday conversation we know quite well what it means for something to be physical, and we can reliably indicate whether something is, in fact, physical. The concept is thereby used to distinguish between things and events that exist (in a way that can be publicly demonstrated), and the various experiences that can only be known to us privately or inwardly. It is this notion of the physical in contradistinction to entirely private, phenomenal, subjective experience that I shall be considering in this paper. A paradigm example of an entirely subjective experience is my acquaintance with sensory colour, such as the redness of a particular shade of red. The demonstration that such experience is entirely subjective is my inability to express or indicate to anyone else what my experience of the particular red colour quality qua quality is (in itself). I can indicate the object whose objective red colour is known to me on the basis of the colour quality. I can indicate the photons that are emitted from the object, the responses that occur in my retina, and the events occurring in my brain. But at no point in that chain of events can I indicate directly to you what it is that I am experiencing as the quality or essence of the colour of the object. The best I can do is to ask you to inspect your entirely subjective experience of the colour of the object I am looking at, and work on the assumption that the colour quality you are experiencing is similar to the one I am experiencing (the likelihood that our qualitative experiences should concur exactly, given the differences in the responses of our respective visual systems, is not high). Perhaps, with a suitable brain-o-meter, we could observe that events of the same class are occurring in both our brains and, given that membership of …