Biological naturalism, the view that consciousness is a systemic property, is a view put forward by John R. Searle as a possible answer to the mind-body problem. There are, of course, several different ‘mind-body’ problems, but the one that most concerns Searle is the relationship between consciousness and physical brain processes.
In this essay I will begin by outlining Searle’s position of biological naturalism and discuss its key strength. I will then look at some common criticisms of the view, particularly the argument concerning the irreducibility of the first-person. Finally, I will briefly look at the view that biological naturalism is actually a form of property dualism, before concluding that Searle’s claim that consciousness is a systemic property is ultimately unconvincing.
Searle doesn’t accept a functionalist definition of mental states because of the problem of qualia – how can we define the subjective “what-is-it-like”ness of experience in terms of functional roles? The famous Chinese Room argument, for Searle, is the nail in the coffin: the man in the room doesn’t actually understand chinese, he’s only following instructions. Similarly, a computer might be functionally isomorphic to a brain – identical in form and relations – but it wouldn’t feel pain. Consciousness, then, is not reducible to a function.
There are some functionalist responses to Searle’s objections, but for the purposes of this essay I will ignore them and assume he is right. His rejection of functionalism is merely a starting point. This rejection of functionalism on the grounds that it cannot account for subjective experience – that a functionalist account is unable to encapsulate all of the phenomenal qualities of experience – gives us a good starting point for a definition of consciousness. Searle claims that consciousness is “irreducibly first-personal”; you cannot understand it all from the third-person; there is an aspect of it that exists only from the first-person perspective. Mental states are only available to the person experiencing them; they are utterly subjective. Unlike in forms of reductive materialism – either ontologically reductive accounts like physicalism / functionalism or analytically reductive accounts such as behaviourism – consciousness cannot be explained from the ‘outside’ by observing it (from the ‘third-person’), but instead only in terms of how they are like from the subject’s point of view.
If consciousness, then, is inherently and irreducibly first-personal, how can we study it? What is it? Searle argues that it is a biological phenomena of the system of the brain as a whole. It’s not a functional property, like functionalists claim, and nor is it reducible to the individual ontologies of each of its states; it is a systemic property, a property of the system as a whole. Systemic properties are common in science. For example, water is a liquid. None of its component molecules are liquids – it is the consequence of the molecules bonding in the way they do to provide liquidness at a system level. In this case, there is a clear and precise relationship between the lower-level feature (molecular structure) and the higher-level feature (liquidness). Searle argues through this analogy that the same holds for consciousness: no individual neuron is a conscious being, but when neurons interact in the right way, the brain as a whole has a conscious state. Consciousness is the result of the brain being structured the way it is and the micro-level brain processes behaving the way they do – if we were able to replicate the brain’s behaviour, we would be able to create consciousness. It is a biological phenomenon; the property of a system of neurons.
A key strength of this account is that it starts at a point that is consistent with our intuitions about the phenomenon. Other physicalist accounts are discordant with our first-person experience, requiring either a sophisticated explanation of how our subjective experience (qualia) occur, or an error theory to explain why our intuitions are mistaken; biological naturalism embraces our first-person experience. Searle is eager to point out that consciousness is subjective and first-person. He also appeals to our intuitions of mental causation; he believes that mental states are causally efficacious.
There are, however, some credible objections to this account of consciousness. There appears to be a significant difference between other systemic properties, such as liquidness, and consciousness. We can give a complete, objective, scientific reason why something liquid is a liquid. We simply study the behaviour of the molecules, thereby ‘reducing’ the phenomenon to what explains it. But Searle is claiming that this is impossible; if the phenomena of consciousness are irreducibly first-personal, then by Searle’s admission the properties of consciousness cannot be physical. Consciousness is not like other systemic properties if it cannot be observed objectively.
Searle rejects this argument. We could redefine consciousness in terms of the underlying physical mechanics, just as we redefined liquidness in terms of the behaviour of molecules. But then we’d be leaving out the phenomena that we’re actually interested in, namely the first-personal conscious experience itself. However, this doesn’t mean that consciousness isn’t physical. We’ve explained that it is a higher-order property of a functioning brain, and when we talk of consciousness we aren’t not talking about brain processes. It’s just that the phenomena that we’re interested in needs to be defined in terms of first-person subjective experience in order for it to be relevant to our line of enquiry. The irreducibility of consciousness is a pragmatic decision, a consequence of what we’re interested in studying, without any real metaphysical implications. We refrain from reducing consciousness to physical, third-person terms, not because we can’t, but because by doing so we lose sight of the phenomena we wanted to study in the first place.
While this response is convincing, we can continue to press the objection. If we start from the bottom-up, we can explain how the behaviour of a certain structure of water molecules results in the higher-order system property of liquidness. However, we cannot do this with consciousness. We are unable to explain how consciousness arises from the physical; the mind-body problem remains. However, we can respond to that easily: in studying consciousness, we must remember that we still know very little about how the brain actually works. As neuroscience develops, we may very well get an explanation of how consciousness arises from the brain as liquidness arises from water molecules. However, I don’t believe this response meets the objection. It side-steps the issue of how an explanation of something in third-person terms can ever be adequate at explaining the qualitative experience of something first-personal.
Another objection to biological naturalism concerns the causal efficacy of mental states. The physical universe is “causally closed,” and if consciousness is irreducible to the physical or material universe, then it can have no causal effects on the physical universe.
Searle anticipates this objection, and provides a response: “it is because of the mistake of accepting the dualistic categories that there even seems to be a problem.” High-level features of a system are able to function causally even though the high-level feature itself is itself caused by and realised in a system of low-level elements. At the macro-level, when a hammer hits a nail, you can tell the causal story as you would normally, in terms of weight, solidity and velocity. However, the story can also be told at a micro-level – in terms of the individual molecules and their energy transfer. These are not two independent stories, but rather two different descriptions of the same story at different levels. Consider the analogous example of an individual raising her arm. We can tell the story at the macro-level of her deciding to raise her arm and the ensuing bodily movement, just as we can tell the exact same story at the micro-level, of her neurons firing in the motor cortex and the secretion of acetylcholine at the axon end plates of the motor neurons. These are not two independent stories, they are two descriptions – of two separate levels – of the same story. This, to me, seems to be a successful response to the problem of causation.
A final question concerns whether or not biological naturalism is actually a form of property dualism. Whilst biological naturalism claims that mental properties can arise from physical states, it also argues that there is a component of mental states that is irreducible and subjective (the first-personal component). Since these states are subjective, and scientific explanations are objective, we are unable to give a full and complete account of the world in scientific terms. We have to discuss mental properties separately. This is the foundation of a separate, dualistic view of consciousness, property dualism.
Searle vehemently claims that it is not dualism. He insists that it is the “inadequacy of the traditional terminology” that makes biological naturalism appear to be property dualism (Searle, 2002, p.61). Traditional philosophical usage of “mental” contrasts it by definition with “physical,” so that taking the mental to be irreducible seems to imply taking it to be non-physical (Feser, 2004). If we jettison this usage, Searle argues, the commitment to property dualism disappears. This move, however, ignores the fact that implicit in Searle’s own argument is that the distinction between the mental and the physical does not come from some arbitrary definition of terms. On Searle’s view, mental phenomena are uniquely subjective and therefore uniquely ontologically irreducible. That is precisely why they are contrasted with physical properties, all of which are reducible! Of course, some philosophers would argue that mental states aren’t actually irreducible, but this is certainly not what Searle is claiming; indeed, his position depends upon it. Searle needs to redefine ‘physical’ to include both the phenomena we usually consider physical as well as the uniquely subjective and irreducible mental states in order for his argument to not be property dualism. But at that point, Searle is just redefining terms to suit his argument. The problem is, ontological irreducibility of subjective mental phenomena is the basis of property dualism. And Searle tries to deny that his account is property dualism whilst clinging to the belief that mental states are subjective and ontologically irreducible.
The biological naturalism account has many positive points. Searle goes to great lengths to establish a new kind of philosophy of mind, reconciling the intuitions we have about day-to-day consciousness while denying dualism and pitching his tent firmly in the field of neuroscience. While he manages to provide a convincing account of mental causation, he struggles to show how we can explain first-personal experiences in third-person terms, and, worse still, fails to show how his account differs from property dualism. I can therefore conclude that Searle does not succeed in establishing his claim that consciousness is a systemic property.