We exist. Therefore strong AI is possible, in that if you were to exactly replicate all of the features of a human, you would have created a strong AI (unless there is some form of Dualism and that you needed whatever a 'soul' is from the 'higher reality' to become conscious).
What things might make Strong AI really really hard, though not impossible?
Maybe a neuron is actually way way more complicated than we currently think, so the problem of making an AI is a lot more complex. etc.
We exist. Therefore strong AI is possible, in that if you were to exactly replicate all of the features of a human, you would have created a strong AI
No, you would have created a human.
If Strong AI turns out to not be possible, what are our best expectations today as to why?
I'm thinking of trying myself at writing a sci-fi story, do you think exploring this idea has positive utility? I'm not sure myself: it looks like the idea that intelligence explosion is a possibility could use more public exposure, as it is.
I wanted to include a popular meme image macro here, but decided against it. I can't help it: every time I think "what if", I think of this guy.