Four objections to materialism

And why they don't work

Materialism and its modern cousin physicalism are points of view in philosophy that posit that everything that exists is related to matter and subject to the laws of physics. Notably this includes consciousness and mental states. There are some subtle differences between these two philosophical traditions, but for the purpose of this post, we shall ignore them here.

Traditionally, there are four main objections to materialism:

1. Theories of panpsychism

2. Quantum mechanics and non-locality

3. The measurement problem in quantum mechanics

4. The Hard Problem of Consciousness

Let’s go through these in details. Panpsychism is the idea that consciousness is a fundamental feature of all matter, that it exists in some form even at the level of fundamental particles, perhaps akin to gravity or electric charge. Some theories such as Integrated Information Theory have tried to generate scientifically testable hypotheses, but none of yet succeeded to provide any convincing evidence in favour of panpsychism. With such a lack of empirical evidence and a failure to explain how such an intrinsic property of matter interacts with the known physical forces, not much credibility can be assigned to this criticism.

Second, quantum mechanics includes the concept of entanglement, where particles or physical objects arbitrarily apart from each other exhibit correlations when their properties are measured that cannot be explained with Newtonian physics. Some people unfortunately mix this up as evidence against Einstein’s theory that no form of information can travel faster than the speed of light. This is in error, as entanglement as well as other seemingly non-local phenomena in quantum mechanics can help to move physical particles or information instantaneously. In conclusion, even though quantum mechanics as many features that are baffling and highly unintuitive in comparison to our everyday experience, there is nothing that disproves materialism. What it does show however that our naïve conception of how the universe works might be fundamentally flawed.

Third, the measurement problem in quantum mechanics is perhaps even more mysterious. Quantum mechanics describes physical systems using a wave function, which represents a superposition of all possible outcomes. For example, an electron can be at multiple positions simultaneously with different probabilities assigned to different positions. However, when we measure the position, we always obtain only one specific outcome. Traditionally physicists call this the collapse of the wave function. One notable experiment showing this phenomenon is the double slit experiment where light particles (photons) or other particles appear to go through two slits in a barrier at once, generating an interference pattern on a screen behind the barrier. However, when particles are measured at each slit, they only ever appear to go through one slit or the other, never both. While some explanations have been advances such as the pilot wave theory or the existence of parallel universes (in the many worlds interpretation), at this stage we have no fully developed and testable theory explaining the measurement problem. However, this does not mean that there isn’t one. Quantum mechanics remains deeply mysterious, but so have many other phenomena throughout the history of human enquiry until explanation were found. At this stage there is no reason to assume we will not eventually be able to explain what is happening. More critically even, there is nothing to indicate that there are non-physical processes occurring here. It merely shows that our theories are still incomplete.

Finally, perhaps the biggest objection to materialism is the hard problem of consciousness. In a nutshell it exposes the mystery that if everything that is happening in the brain can be explained with physical processes why then do we have the experience of feeling emotions, joy and pain, why does it feel being ourselves the way it does. At this stage, we cannot explain how subjective experiences arise out of these electrochemical processes in the brain. Many philosophers have therefore posited that this disproves materialism, that there is something non-physical happening in the brain. This could go as far as assuming the existence of a soul or other forms of spirituality. The aforementioned panpsychism is another approach to explain consciousness. All of these approaches stumble at the same step. Given that consciousness that can be influenced by physical factors such as intoxicants, anaesthetics or indeed physical trauma, and vice versa given that consciousness appears to direct physical actions (although this is potentially more controversial than the former), we have never found any interaction point, any method, any indication how non-physical processes or objects interact with physical ones. The burden of proof therefore has to be with those who posit the existence of non-physical phenomena. At this stage the scientifically far more likely scenario is that we simply do not yet understand enough about information processing patterns and how they relate to subjective experiences. Perhaps the emergence of conscious AI would provide some form of proof. However, what we really need is a testable theory that can allow the measurement of the existence of consciousness from the outside. What such a theory should look like will be the subject of a future blog post.

For now, materialism is surviving all the different objections to it. However, we can conclude that our current understanding of the universe in terms of the laws of physics and related sciences is incomplete.