One of the main reasons behind the appeal of panpsychism is the fact that physical sciences, while making progress in understanding and even mapping how brain states are related to mental states, have yet to explain why all of that is accompanied by the distinctive ‘what’s-it-likeness’ of subjective experience – usually called phenomenal consciousness.
For example, when I step on a Lego, why is that physical event accompanied by unbearable hellish pain and misery in my experience? It seems that a being could exist that acts in the exact same manner as I do when I step on a Lego – curses a lot and cries – but without them experiencing the quality of pain internally, as part of their conscious experience. That is, they would not actually feel pain, just behave exactly as if they did.
Evolutionarily speaking, that being would not be better or worse off than me, so it is unclear whether one could simply explain phenomenal consciousness away by invoking the process of evolution. Generally speaking, it seems that any attempt at explaining phenomenal consciousness solely in terms of physical facts will fail to produce a satisfying account of why there is something it is like to be me.
As David Chalmers put it, issues of explaining how brain processes underlie cognition and behaviour fall under the easy problems of consciousness. Granted, they are certainly not easy and the disciplines that address them are as complex as they are impressive. However, in principle, there is nothing that makes it impossible for the neuroscientist to know how a particular brain process explains a particular behavioural act. A perfect neuroscience that has reached the ultimate peak of its development or an omniscient God would both have answers to all of the so-called ‘easy’ problems of consciousness.
When it comes to explaining why those brain states are accompanied by phenomenal consciousness, several difficulties arise. This is what Chalmers calls the hard problem of consciousness. The common methodological assumption of science is that phenomenal consciousness must be explained in terms of facts and processes that are themselves non-conscious. But if phenomenal consciousness differs in kind from the purely physical and structural, then how could it be accounted for solely in terms of such physical and structural facts? In other words, if phenomenal consciousness is a real phenomenon, in and of itself, then how could it emerge from things that are entirely non-conscious? How could something ontologically novel pop into existence at higher levels, such as the human brain, without already being present at lower levels?
This would amount to a form of radical emergentism, where a higher-level property emerges from lower levels as something entirely new, without actually being present at lower levels in the first place. Liquidity, for example, might seem like a property that is only present at the higher level. Water is liquid, but water molecules, in and of themselves, do not have the property of liquidity. Does that mean that liquidity is a radically emergent property, not present at the lower level of molecules? The answer is no. Liquidity simply is a particular way in which molecules interact – by sliding past each other. That means that if we knew everything about relations obtaining between water molecules, we could deduce that the result of those interactions is liquidity at the higher level (e.g. of water in a cup). To restate: liquidity is intelligibly reducible to facts obtaining at the lower level, meaning that liquidity simply is molecular interaction, as well as being intelligibly deducible from facts obtaining at the lower level, meaning that knowledge of those facts guarantees knowledge of higher-level facts. This is a weak rather than a radical form of emergence.
Is phenomenal consciousness a weakly emergent property? Are facts about phenomenal consciousness at the higher level intelligibly reducible to or deducible from facts pertaining to the lower level? If the entities at the lower level are entirely non-conscious, then no – that would be a case of radical emergence. As a way of avoiding radical emergence, the panpsychist argues that we should postulate consciousness at the lowest level of reality. If we do that, then we open up a way for phenomenal consciousness to be treated as a weakly rather than a radically emergent property.
To argue for that move, Thomas Nagel presented the following four premises:
- Material Composition – Living organisms are complex material systems with no immaterial parts. The matter composing us is not special; the matter composing any material entity, if broken down far enough and rearranged, could in principle be incorporated into a living organism.
- Realism – Mental states are genuine properties of living organisms.
- No Radical Emergence – All the properties of a complex organism are intelligibly derived from the properties of its parts.
- Non-Reductionism – The mental states of an organism are not intelligibly derived from its physical properties alone.
Nagel claims that if all of these premises are true, then matter must involve non-physical properties that intelligibly imply the existence of mental states at higher levels (in organisms).
Similarly, Galen Strawson has argued against radical emergence:
Emergence can’t be brute. It is built into the heart of the notion of emergence that emergence cannot be brute in the sense of there being absolutely no reason in the nature of things why the emerging thing is as it is (so that it is unintelligible even to God). For any feature Y of anything that is correctly considered to be emergent from X, there must be something about X and X alone in virtue of which Y emerges, and which is sufficient for Y.
Strawson and Nagel’s claims constitute the anti-emergence argument for panpsychism. The upshot is this: if we take consciousness seriously, as a real phenomenon that cannot be reduced or eliminated by appealing to purely physical facts, then we must posit it at the lowest level of reality if we ever want to hope for an intelligible explanation of how it emerges at higher levels. The resulting theory is panpsychism, the claim that consciousness is a fundamental feature of reality. The more extreme conclusion is that one must be a panpsychist if one is not an eliminativist or a reductionist about consciousness since only panpsychism can open the door for an intelligible explanation of consciousness.
David Chalmers – Facing Up to the Problem of Consciousness.
David Chalmers – The Conscious Mind: In Search of a Fundamental Theory.
Galen Strawson – Realistic Monism: Why Physicalism Entails Panpsychism.
Philip Goff, William Seager and Sean Allen-Hermanson – Panpsychism.
Thomas Nagel – Mortal Questions.