Suppose we were naïve observers, given the following data, and asked to draw a conclusion.
We see people gather at a busy bus stop several times a day. At first one person, then another, and another, until they form a group. Then a bus arrives, the people get on board, and the bus takes them on their journey.
We might ask, what causes the bus to arrive? Every time the bus arrives is preceded by a group of people gathering at the bus stop. It would be perfectly rational, as a naïve observer, to conclude that the people gathering at the bus stop is what causes the bus to arrive. Hundreds of observations support this simple conclusion.
Of course we know that’s not how it works. Buses have timetables, and drivers who try to stick to timetables, and passengers who read timetables and coordinate their actions according. The people gathering at the bus stop do not cause the bus to arrive. They gather at the bus stop because they know the bus is coming.
But if you didn’t know about timetables, and you didn’t know that people gather because they know a bus is coming, it would be perfectly reasonable to draw the other conclusion: that people gathering at the bus stop is what is causing the buses to arrive.
The question is, are we making a similar mistake with consciousness and the brain? We know that events in the brain are closely correlated with thoughts and emotional states. We then make what seems to be the reasonable deduction that the physical events in the brain are what cause us to feel and think certain things. We have no idea how a physical event could cause a thought or a feeling, but we trust there must be some causal link direct from one to the other.
But what if we are looking at it the wrong way? People gathering at a bus stop do not cause a bus to arrive, and physical events in the brain do not cause feelings or thoughts. In each case the two things coincide because of a deeper cause below the surface.
The reason this possibility should be taken seriously is because we have no rational explanation for why or how a physical event can cause a feeling or a thought. Saying an event in the brain causes a thought to occur takes two different kinds of phenomena and links them mysteriously and without explanation.
Maybe there is something deeper going on here that we do not understand.