Originally Posted by
Brian Rush
It means what we observe to be true. In this particular case I'm not talking about what we can observe versus what we can't, I'm talking about accepting what we observe versus insisting that it's not true. Thus, any limitations of the method don't arise. We observe that brains think. We observe that people with damaged cerebral cortexts experience cognitive difficulties. We observe that stimulating a part of the brain electrically produces cognitive, memory, and emotional responses.
Note that I'm not talking at the moment about anything else that may be observed with any other method, merely about the fact that these things are observed in this way. And so, regardless of what else we observe, regardless of what is "beneath the surface," and regardless of what metaphysical theory we prefer to account for what the brain is in any cosmic sense, the fact remains that we observe brains thinking. That fact must remain with us regardless of what else we do.
We observe that when people suffer cerebral cortex damage of certain kinds, they have difficulty using language, performing mathematical calculations, and reasoning logically. All of these are normal observed concommittants of reported experienced mental states. Either you accept that they are associated with, and reliable indicators of, those mental states or you do not. If you do, then you must accept the evidence that brains think.
If you do not, then you should consider the logical consequences. It means that when you hear someone talking, this is not an indication that they are aware in any subjective way of using language. It means that when a student performs a mathematical calculation in class, that student could be an automaton not really thinking mathematically at all. It means there is no connection whatever between people's behavior and their minds. Are you prepared to go that far out on a limb in defense of what you want to believe?
This has nothing to do with assumptions. It has, rather, to do with the entire corpus of knowledge gained from observation. If we accept the literal reality of "spirits," we are left with a huge number of unanswered questions, including what exactly a "spirit" is, and how to fit it in with the rest of the known universe. As such, it becomes far more complex than an explanation which does not require such a hypothesis.