For most of the twentieth century a “brain-first” approach dominated the philosophy of consciousness. The idea was that the brain is the thing we really understand, through neuroscience, and the task of the philosopher is try to understand how that thing “gives rise” to subjective experience: to the inner world of colours, smells and sounds that each of us knows in our own case. This philosophical project has not gone all that well–nobody has provided even the beginnings of a satisfying solution to what David Chalmers called “the hard problem” of consciousness.

More recently a quiet revolution has been occurring in philosophy of mind which aims to turn the brain-first approach on its head. According to the view that has come to be known as “Russellian monism,” physical science tell us surprisingly little about nature of the brain (more on this below). It is the nature of consciousness that we really understand–through being conscious–and hence the philosophical task is to build our picture of the brain around our understanding of consciousness. We might call this a “consciousness-first” approach to the mind-body problem. The general approach has given birth to a broad family of specific theories outlined in numerous recent publications. Suddenly progress on consciousness looks possible.

The essence of Russellian monism

The conscious mind and the physical brain seem on the face of it to be wildly different things. For one thing, conscious experiences involve a wide variety of what philosophers call “phenomenal qualities.” This is just a technical term for the qualities we find in our experience: the redness of a red experience, the itchiness of an itch, the sensation of spiciness. A neuroscientific description of the brain seems to leave out these qualities. How on earth can quality-rich experience be accommodated within soggy grey brain matter?

The Russellian monist solution, inspired by certain writings of Bertrand Russell from the 1920s, is to point out that physical science is in fact silent on the intrinsic nature of matter, restricting itself to telling us what matter does. Neuroscience characterises a region of the brain in terms of (A) its causal relationships with other brain regions/sensory inputs/behavioural outputs and (B) its chemical constituents. Chemistry in turns characterises those chemical constituents in terms of (A) their causal relationships with other chemical entities and (B) their physical constituents. Finally, physics characterises basic physical properties in terms of their causal relationships with other basic physical properties. Throughout the whole hierarchy of the physical sciences we learn only about causal relationships.

And yet there must be more to the nature of a physical entity, such as the cerebellum, than its causal relationships. There must be some intrinsic nature to the cerebellum, some way it is in and of itself independently of what it does. About this intrinsic nature physical science remains silent.

Accepting this casts the problem of consciousness in a completely different light, and points the way to a solution. Our initial question was, “Where in the physical processes of the brain are the phenomenal qualities?” Our discussion has led to another question, “What is the intrinsic nature of physical brain processes?” The Russellian monist proposes answering both question at once, by identifying phenomenal properties with the intrinsic nature of (at least some) physical brain processes. Whilst neuroscience characterises brain processes extrinsically, in terms of what they do, in their intrinsic nature they are forms of quality-rich consciousness.

Two Arguments for Panpsychism

Russellian monism is a general framework for unifying matter and mind and thereby avoiding dualism: the view of Descartes that mind and body are radically different kinds of thing. But how to fill in the details is much debated. Many have found it natural to extend Russellian monism into a form of panpsychism, the view that all matter involves experience of some form, bringing a new respectability to this much maligned view. There are essentially two arguments for this extension, one of which I don’t accept and one of which I do.

The first is the “intelligible emergence argument,” an ancient argument for panpsychism championed in modern times by Galen Strawson. The idea is that it is only by supposing that there is consciousness “all the way down” to electrons and quarks that we can render the emergence of human and animal consciousness intelligible. Experience can’t possibly emerge from the utterly non-experiential, according to Strawson, so it must be there all along. One difficulty for this argument is that even if we do attribute basic consciousness to the smallest bits of the brain, it’s still not clear how to intelligibly account for the consciousness of the brain as a whole. How do the interactions of trillions of tiny minds produce a big mind? This is the so-called “combination problem” for panpsychism, and until it is solved it’s not obvious that the panpsychist Russellian monist has an advantage over the non-panpsychist Russellian monist when it comes to explaining the emergence of human and animal consciousness.

I favour instead what I call “the simplicity argument” for panpsychism. Whilst in the mind-set that physical science is giving us a complete picture of the universe, panpsychism is implausible, as physical science doesn’t seem to be telling us that electrons are conscious. But once we accept the basic tenets of Russellian monism, things look quite different. Physical science tells us nothing about the intrinsic nature of matter; indeed arguably the only thing we know about the intrinsic nature of matter is that some of it, i.e. the brains and humans, have a consciousness-involving nature. From this epistemic starting point, the most simple, parsimonious speculation is that the nature of matter outside of brains is continuous with the nature of matter inside of brains, in also being consciousness-involving. This may seem like an insubstantial consideration, but science is strongly motivated by considerations of simplicity. Special relativity, for example, is empirically equivalent to its Lorenzian rival but favoured as a much simpler interpretation of the data.

Against neuro-fundamentalism

Some philosophers–I call them “neuro-fundamentalists”–think the only way to make progress on consciousness is to do more neuroscience. These philosophers have an exceedingly limited view of how science operates, as though it’s simply a matter of doing the experiments and recording the data. In fact, many significant developments in science have arisen not from experimental findings in the lab but from a radical reconceptualization of our picture of the universe formulated from the comfort of an armchair. Think of the move in the Minkowski interpretation of special relativity from thinking of space and time as distinct things to the postulation of the single unified entity of spacetime, or Galileo’s separation of the primary and the secondary qualities which paved the way for mathematical physics. My hunch is that progress on consciousness, as well of course as involving neuroscience, will involve this kind of radical reconceptualization of the mind, the brain, and the relationship between them. Russellian monism looks to be a promising framework in which to do this.

Featured image credit: Abstract lights. Image by Little Visuals. Public domain via Pexels.