First Person Authority

The argument

Dualism is defended here by pointing to an asymmetry in how two kinds of state are known. Consider the moment of deciding that one needs a glass of water. No inference is involved, and no assumption based on evidence: a person does not need to calculate the time since their last glass of water in order to establish that they need another, nor feel their tongue and deduce from its dryness that they must be thirsty. The knowledge arrives without any of that intermediate work being done. This is what first person authority means. Mental states are knowable without inference or experience, in the sense that the person whose states they are does not have to gather evidence about them or reason from anything else in order to reach them. The route is direct, and because it is direct there is no step at which it could go astray. Physical states are known in quite a different way. What one knows about one's body, or about anything else in the world, arrives through observation, and physical states can be deceptive and prompt error: the evidence may mislead, the inference drawn from it may be faulty, and the conclusion may turn out false even where the process that produced it looked sound. The conclusion is drawn from the gap between those two routes. If mental states are available to their subject immediately and without the possibility of that kind of mistake, while physical states are available only through a fallible procedure, then the two are not simply different subject matters known in the same manner, but appear to be different kinds of thing, distinguished by the sort of access each permits. That difference is what dualism asserts, and first person authority is offered as the evidence for it.

Context

The dualist position hinges on the idea that human beings are made up of two components; the physical and the non-physical. Our body and brain, everything we can touch, move, feel, and manipulate, lies within our physical construct. But we also have a non-physical mind. Our consciousness, emotions, desires, and experiences occupy the mind. They cannot be observed, touched, or perceived, but they still exist in the non-physical realm. While there are many different brands of dualism, the core idea of “dual” entities- a physical and a non-physical- connects them all. Plato was one of dualism’s earliest proponents. In his Phaedo, Plato promoted the idea that humans had eternal “Forms” which provided intellect and gave us the capacity for understanding. He suggested that our immaterial Forms were imprisoned within our physical bodies

Premises

Counter-arguments

Neurological Correlation Critics of dualism have pointed to neurology and neuroscience as evidence that dualism is misplaced in its approach. When we have a mental thought, for example, imagining myself walking through the front door to my home, a certain part of the brain which correlates to special recognition becomes active. We can clearly see this in MRI scans. Even something we know intrinsically, like needing a glass of water, has corresponding neurological activity. Similarly, when I experience pain, there is c-fibre stimulation inside the brain. This suggests that there is a physical process behind each thought and that rather than mental states occupying the realm of the non-physical, they are nothing more than a collection of neurons firing in the brain.

Rejecting the premises

Our mental states correspond to physical activity in the brain. Therefore, our mental states are not non-physical, they are physical. Therefore, humans are not made of two substances. They are only made of physical matter.