That's religious dualism, but you're not taking into account the full range of philosophical debate. There certainly are dualists who do not invoke the supernat

That's religious dualism, but you're not taking into account the full range of philosophical debate. There certainly are dualists who do not invoke the supernatural, particularly with regards to consciousness. But in this case, the claim is that functionalism can serve as dualism, when it treats the body as irrelevant to the functioning of the mind. I gave you examples from science fiction. Even the idea of mind-uploading could be considered functional dualism, as it assumes there is something mental which can be copied from the neural/biological, implying the mind is separate.