- What's in your view is the difference between our perception, like how we think the world is, and reality? Do you think there's a huge gap there? Like we delude ourselves that the whole thing is an illusion, just everything about human psychology, the way we see things, and how things actually are.

In all the things you've studied, what's your sense? How big is the gap between reality and perception? - Well, again, purely speculative. I think that we will never know the answer. We cannot know the answer. There is no experiment to find an answer to that question. Everything we experience is an event in our brain.

When I look at a cat, I'm not even, I can't prove that there's a cat there. All I am experiencing is the perception of a cat inside my own brain. I am only a witness to the events of my mind. I think it is very useful to infer that if I witness the event of cat in my head, it's because I'm looking at a cat that is literally there and has its own feelings and motivations and should be pet and given food and water and love.

I think that's the way you should live your life. But whether or not we live in a simulation on the brain in a vat, I don't know. - And do you care? - I don't really, well, I care because it's a fascinating question. And it's a fantastic way to get people excited about all kinds of topics, physics, psychology, consciousness, philosophy.

But at the end of the day, what would the difference be? If you-- - The cat needs to be fed at the end of the day. Otherwise, it'll be a dead cat. - Right, but if it's not even a real cat, then it's just like a video game cat.

And right, so what's the difference between killing a digital cat in a video game because of neglect versus a real cat? It seems very different to us psychologically. Like I don't really feel bad about, oh my gosh, I forgot to feed my Tamagotchi, right? But I would feel terrible if I forgot to feed my actual cats.

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