In the twentieth century, Jean-Paul Sartre famously said that existence precedes essence, which is the reverse order of what the Medieval philosophers believed. In this line of thinking, a thing first exists, and then due to its form of existing, it has essence bestowed upon it by observers. This is where the Existentialist idea of radical freedom came from. In the Medieval philosophy, you were your essence first, and it was God that bestowed upon you your existence. But that means your essence is immutable. In Existentialism, it is you that creates your essence to be what you want, and your essence is only determined by what you do, not by your intentions. What this idea ultimately concludes is that there is nothing special about an existing object apart from the meaning given to it by minds, or being-for-itself in Sartre’s parlance, denoting the objectness of the mind. But if the mind is an object, then what is it about the mind that makes it special, allowed to bestow meaning on the objects around it?
In this section I discuss why materialism offers only an incomplete explanation for consciousness.
The materialist view of mind-body dualism has usually been to dismiss it. Certainly, with our current scientific knowledge, it is not parsimonious to add a non-physical “mind” to the equation. In this conception, the mind is a product of the physical substrate. This can be observed when one takes a mind-altering drug – a physical molecule binds to receptors in the brain, altering the way the physical brain functions, which is the same as altering the mind.
Neuroscientists like Antonio Damasio have even formulated theories of consciousness that require the presence of a body in order for consciousness to exist, which further unifies the mind-body into a single material Substance, which may lead to personality changes from organ transplants. This conception if the mind-body relationship has consequences for determinism, but that is beyond the scope of this work.
The materialist answer has a different sense of being right. To say that a mind or soul exists does not really answer the question, and in fact begs the question of what a mind or soul is. Although one may experience being a mind, a mind has never been defined or measured. It is impossible to even know whether other minds beside our own mind even exist, so how can one say for sure that minds exist independent of the bodies they inhabit? And the cause-effect relationship of the body-mind can and has been repeatedly tested via chemical intervention. To my knowledge, there is not a drug in existence that interacts with the brain in a measurable way that does not have some measurable effect. Therefore, the materialists say, the mind and body are indistinguishable from one another.
In scientific terms, the mind-body relationship is often characterized in terms of a computer: the body is hardware and the mind is software. Detractors of this analogy accuse its proponents of putting too much stock into the comparison. There is not an apples-to-oranges equivalence between body and hardware much less mind and software and trying to fit theories of mind into computer analogies is harmful to progress in philosophy of mind.
That being said, it is still difficult to not see a mind-body duality at play here, even if it is not a mind-body independence. While the modern Christian conception of mind-body dualism may allow for the mind to exist independent of the body, the mind-as-software conception does not. What is interesting, though, is that with mind-as-software, the software can run on many different types of hardware. A completely unified mind-body monism would require that only body A could have mind A and only body B could have mind B. Indeed, to say that body A has mind A is incorrect, because body A is mind A. But if mind A is merely software, then mind A could conceivably “run” on body A, or body B, or body C etc. This is called substrate independence.
But is substrate independence, when it comes to the mind, one of those blind spots we’ve thrown in our own way by using the computer analogy to understand the mind? This is important when it comes to the question of whether a general artificial intelligence is conscious or not, or whether humans will ever be able to “upload” their consciousness onto a computer. The computer analogy for the mind-body relationship assumes that cognition and consciousness are forms of information processing. Computer A that is processing the same information as human brain A, regardless of the physical “stuff” with which the information processing is being done by the computer, will have a mind that is indistinguishable from human brain A. If this is true, then a general artificial intelligence that processes information similarly to a human brain will be conscious, and a person will theoretically be able to “upload” their mind onto a computer.
This answer to the mind-body relationship has both the intuitive feeling of being a mind “inhabiting” a body while also being dependent on the body. While the analogy may be imperfect, and possibly even deleterious in the end, it still appears more accurate than the previous two. Unlike the Christian conception, the mind-as-software analogy does not simply push the answer of “what is mind” back into the realm of the unknown without explaining how mind and matter interact. Unlike the materialist conception, it allows for an emergent property that, while dependent on the physical substrate, is not necessarily physical itself. However, it still fails to explain how qualia exist. There is still no ontology for what is meant by software. Ultimately, the mind-as-software analogy, with its substrate independence, is still a materialist idea.
Materialism says that the mind and the brain are one in the same. The mind is material. For obvious reasons this explanation is unsatisfactory and incomplete. If the mind is material, then what is the experience of red made of? Or the experience of hearing Behemoth’s “Blow Your Trumpets Gabriel” for the first time? Or the feeling of joy? All a materialist can say is that a particular brain state is correlated with these things, but there is no materialist answer to what those experiences actually are.
If the mind was made of the same material as the physical world, then it could be measured. Something like red would have mass. If a tree fell in the forest and nobody was there to hear it, it would definitely make a sound. The difference between the smell of roses and the smell of tulips could be quantified. The taste of potato chips would exist while nobody was actually tasting them lest we believe some physical thing is popping in-and-out of existence.
The pattern of brain connections would be sufficient to explain humans from a behaviorist perspective, but it is insufficient for explaining phenomenology – the actual internal content of the mind. Something is missing. Materialism is incomplete.