How do we know that an artificial intelligence is even possible? I understand that, in theory, assuming that consciousness is completely naturalistic (which seems reasonable), it should be possible to make a computer do the things neurons do to be conscious and thus be conscious. But neurons work differently than computers do: how do we know that it won't take an unfeasibly high amount of computer-form computing power to do what brain-form computing power does?

What prevents you from making a meat-based AI?