> It's because it is effectively a computer. Not in the vague sense of "it has stuffs connected to stuffs and there's electricity involved", but in the more specific sense that it takes inputs, produces complex outputs, has clearly identifiable hardware and indirectly identifiable software. It even has internal structure we're only beginning to understand, but that we know enough about to reasonably infer what computations happen where. There's little reason to assume there's some metaphysical mystery here, as exactly zero other things in the universe that we studied since the dawn of humanity turned out to be magic.
You're conflating the ability to compute with ontology. Computers compute. That's all they do. They're programmed to do only that. Humans have other abilities, such as imagination, that are not computational. Computers cannot imagine, not because of limited hardware or software; they can't imagine because they only compute. Imagination isn't computational. All throughout your response you are using the terminology of computers and software as if they are completely intuitive, but we have other terminology to define those things: medical terms define parts as the brain as parts of the brain not as hardware because that's a metaphor; the cerebelum is like this part of the computer. What they are is not the same as what they can do. That's not some magical mystery, or even obscure metaphysics. A car's horsepower is not in its carburetor, or its gas, or its manifold, because the horsepower of a car is what it can do, its an ability, a power. In the same sense the brain can compute, but that doesn't mean it is a computer.
What else could it be? A brain. Animals have them. They are not computers. But they can compute. The field of computer science and software development only slightly aligns with studying the brain.
> If I know the limit of applicability of my computer knowledge, I sure can comment on brain and consciousness.
Yes and when it is no longer applicable it is no longer right or wrong: it's just assumption. That you can fuzzily attach assumptions to arguments about the brain does not mean the brain is a computer. It means you can fuzzily model the brain on a computer, but that model will have glaring gaps. You can build from your assumptions but you have to accept the limitations of that assumption. Assuming the brain is a computer comes with glaring limitations.
You're conflating the ability to compute with ontology. Computers compute. That's all they do. They're programmed to do only that. Humans have other abilities, such as imagination, that are not computational. Computers cannot imagine, not because of limited hardware or software; they can't imagine because they only compute. Imagination isn't computational. All throughout your response you are using the terminology of computers and software as if they are completely intuitive, but we have other terminology to define those things: medical terms define parts as the brain as parts of the brain not as hardware because that's a metaphor; the cerebelum is like this part of the computer. What they are is not the same as what they can do. That's not some magical mystery, or even obscure metaphysics. A car's horsepower is not in its carburetor, or its gas, or its manifold, because the horsepower of a car is what it can do, its an ability, a power. In the same sense the brain can compute, but that doesn't mean it is a computer.
What else could it be? A brain. Animals have them. They are not computers. But they can compute. The field of computer science and software development only slightly aligns with studying the brain.
> If I know the limit of applicability of my computer knowledge, I sure can comment on brain and consciousness.
Yes and when it is no longer applicable it is no longer right or wrong: it's just assumption. That you can fuzzily attach assumptions to arguments about the brain does not mean the brain is a computer. It means you can fuzzily model the brain on a computer, but that model will have glaring gaps. You can build from your assumptions but you have to accept the limitations of that assumption. Assuming the brain is a computer comes with glaring limitations.