THE MIND-BODY PROBLEM
Matter Causes The Mental
Written by Dr. Nash Popovic
Although the starting point is matter, this is a very different perspective from reductive materialism. Its proponents acknowledge that the mind is irreducible even if it is the result of the brain. Therefore, the mental, as something distinct from matter, does exist, which already makes this position a form of (‘weak’) dualism. The most popular view, asserting that the mind arises from the brain complexity, is called emergentism (advocated by Sperry, Popper, Scott, and many others).
The assumption behind this position is that a combination of simple structures can give rise to some qualities that their constitutive elements do not have. A simple example is the wetness of water that emerges from non-wet molecules of hydrogen and oxygen. More broadly, the idea is that physics gives rise to chemistry, chemistry to biology, biology to the brain and the brain to consciousness – but, crucially, none of them can be reduced to their precursors. This is a big improvement on reductive materialism because emergentism can account for subjective experiences, and perhaps even for the non-physical properties of the mental. However, it has some other shortcomings.
- Emergentism does not explain why and how the brain gives rise to mind, but simply assumes that it happens. Not only does the question why the complexity of the brain would lead to consciousness remain unanswered, but also why the complexity increases at all. Considering that emergent systems are always open systems, it is possible that factor(s) external to the system force this increase. If this proposition is taken on board, the conditions and factors that contribute to the emergence of consciousness would need clarification, as they are far from obvious.
- The assembly of neurons and other cells that make up the brain undoubtedly produce some new qualities (e.g. an equivalent to the wetness of water would be the sponginess of the brain). However, the mind is different. Its phenomenal properties appear sharply dissimilar to those of the brain. It can be expected that the increased complexity of the nervous system would allow more complex processes in the brain to occur, but it seems implausible that sentient, experiencing entities could spontaneously evolve at one point out of wholly insentient, non-experiencing substance.
- There is no reason to believe that these properties are specific to human beings. True, the mental life of other organisms may be much more limited, but that does not mean that they are just carbon based robots that don’t have any experience. In fact, as far as observation can be relied on, it seems that even some one-cell organisms exhibit behaviour hinting that they are capable of experience and that they can be pro-active. If this is true, then the ability to experience, in addition to some other mental qualities, cannot be the result of the brain complexity. William Seager, who specialises in philosophy of mind, concludes:
If consciousness is not reducible then we cannot explain its appearance at a certain level of physical complexity merely in terms of that complexity and so, if it does not emerge at these levels of complexity, it must have been already present at the lower levels. (1995, p.279)
- Even if it is accepted that consciousness emerges from brain complexity, how matter affects the mind needs an explanation. There is no reason to believe that physical-to-mental causation is easier to understand than mental-to-physical causation. The latter though is more controversial, so we need to examine it more closely.
Mental causation (the mind influencing the brain) is not really an issue for true materialists because they simply denying that the mind exists. However, for those who recognise that it is mistaken to exclude the mental, this is a big problem as it challenges assumptions such as that the universe only operates according to natural laws. Not surprisingly, denying that the mental can be causal has been explored as an option. This is called epiphenomenalism. From that perspective the unique properties of mind are accepted, but mind is considered a result of brain activity to the extent that it is determined by natural laws. Mind does not influence the body/brain in any way, so choice and agency are illusions. Qualia are acknowledged, but rendered irrelevant. All the processes within an individual along with global processes such as evolution would take place anyway, whether living organisms were aware or not. There are several difficulties with this view:
- If mental events are just epiphenomena that do not have any effect, it is hard to understand why it seems that they play such an important part in evolution, human society and the lives of every individual. It is incredible that human beliefs and desires have nothing to do with actions, and that civilization would have developed even if no humans had ever acted upon their conscious thought.
- As in the case of other physical objects, brain activity cannot be determined by future projections. Yet, at least some actions seem to be based on decisions that rely on predictions and expectations, and they are of a distinctly mental character. If this is just an epiphenomenon, the question can be raised why the mental process of making a choice (e.g. when faced with two alternate means to achieve a goal) exists at all.
- To broaden this question in the context of the evolutionary perspective, if consciousness is an ephemeral by-product, why would it appear in the first place? The mind has too important a role to be seriously considered as a merely accidental by-product.
- Besides common experience, there is also substantial empirical evidence (which will be considered shortly) that clearly shows that mental events can affect the brain and body.
Some emergentists (e.g. Popper) accept that the mind can affect the brain, but this has an overtone of circular causation: the brain creates the mind that in turn affects the brain. This would necessitate that the mind (although the result of the brain) has a relative independence from the brain. Properties that are intimately related to an object (e.g. the colour of a flower or music from an instrument) cannot affect this object above and beyond what it already is or does. How it is possible for the mind to be created by the brain and then sufficiently separated so that it can influence the brain, remains mysterious within the emergentist perspective.
Although it is based on an assumption rather than explanation, and despite the above contentious issues, emergentism can still be a highly useful concept. The main charge against this perspective is not so much in what it claims, but its incompleteness. It can be accepted that the complexity of the brain enables some processes associated with mentality. It is even plausible that such processes can have qualities that appear non-physical. Neuroscientist Karl Pribram, for example, convincingly argues that brain waves may create something like holographic images. However, even if this is accepted, it is not enough. TV stations are also complex systems that produce wave forms that can be transformed into images, but nobody seriously considers that they are conscious. Moreover, what would their use be if something else does not exist to ‘pick up’ these waves? This is missing in emergentist theories. Their world looks like a place with a lot of radio or TV transmitters without radios or TVs to receive their signals.
Considering all these points, the conclusion seems inevitable that if the idea of emergentism is pushed far enough, it is likely to end up in one form or another of either dualism or materialism, with all the additional problems that these theories have.