博客來[2025 updated edition: new chapters on why AIs cannot be conscious, the nature of evil, the place of evolution, and the natural-unnatural equivalence fallacy]
To explain consciousness we must explain not just sensations but how a three-dimensional world is perceived without relying on an inner eye (or homunculus) that can make sense of depth cues etc. Both problems are tackled here as well as language, aesthetics and morality.
The text systematically and ruthlessly dismantles the apparent mechanism of the inner eye (or the homunculus) and shows how all thought and experience and the apparent individual point of view can be accounted for in terms of fundamental quanta of sensation, before going on to show how these remaining basic units of sensation are not (and cannot be) emergent phenomena but must be part of a field effect.
The strategy for the text is to systematically remove any and all conceptual need for a homunculus in the explanation of consciousness, and to scrutinize what must be the case for what remains.
Step One - Perceptions and the Brain
Preamble A:
In everyday discourse about our experience, the content of perception-the pale blue of a region of sky, the tone of the bass guitar in the beat of a dance track, or the sweet almond flavour of marzipan-might be thought of as distinct from the perceiving since I can choose where I focus my attention: on the view through a restaurant window, on the music coming from the café opposite, or on the marzipan coating of the slice of Battenberg cake I am eating.
However, let us for the purpose of this enquiry start by treating the content of perception and our experiencing that perception-the perceiving, as it were-as inseparable. There is no content without the experience; there is no experience without the content. For our purposes, the perceiving is distinct from the deliberate, or otherwise, action of setting the focus of one’s attention here or there-on the cake or on the music.
Preamble B:
It is ultimately an aggregation of these content/perceiving pairings that constitutes the totality of our conscious awareness. Which is to say that any other aspect of our brain’s conscious processes: the focussing of attention, acts of will, or anger, greed and so on must either be incorporated into the scheme as content/perceiving pairings themselves, or be explicable in terms of some arrangement of content/perceiving pairings.
Which is to say, there is nothing in our consciousness beyond these content/perceiving pairings, so every conscious experience must be capable of expression in terms of some or other or set of content/perceiving pairings.
Idea:
Perceptions belong to the brain, are generated by the brain, are private to the brain, exist only within the brain, and do not extend into the external world beyond our bodies.
Elaboration:
The sky is not blue. Rather: photons of light of certain frequencies arrive on the backs of our eyes from the atmosphere. Light receptor cells in our eyes then send electro-chemical signals into the brain, and the brain generates the sensation of some or other colour in response to the electro-chemical signals.
Our perceptions are generated by our brains; we do not swim in a sea of perceptions picking up those useful to us as we pass through them (or them through us).
Corollary:
At first blush, the perceptions described here accord with the philosophical concept of Secondary Qualities.
