You are assuming that mind = brain. You are also assuming that the only rational beings are human beings - without explaining how the power of reason originated.
I assume mind >= brain and one cannot prove its mind>brain.
And why is explanation relevant?
Human beings are or arent’t the only rational beings. Whatever of both is true does not depend on whether i have an explanation.
In that case human philosophy would be restricted to physical reality, as all thoughts would be nothing but specific interactions inside a human brain.
And?
Neither mind > brain nor mind=brain contradicts anything i know, so i cannot say which is true.
That is a metaphysical principle without which science wouldn’t be possible.
Its not a metaphysical principle, its a property of this universe. Of course noting or at least suggesting the assumption of this property is an important step. Small children do this since ages, fortunately adults got the idea as well.
Neither hunger nor any other physical state explains logic.
Which is not scientifically explicable.
I haven’t questioned the existence of a real world. I have simply pointed out that physical causes do not explain insight and the power of reason.
And why is the lack of explanation important?
It would only be relevant, if we had a perfect understanding of the functioning of the brain and yet could not explain what our brain produces,e.g. insight aand power of reason, and if we would fail to create a human-like AI.
Then and only then the lack of explanation would show, that either we still miss some material aspect of the brain or, in case that can be excluded, mind > brain.
Just because A cannot be explained based on information B does not mean C is true.It is also possible that C is wrong and information D was missing and B+D explain A.