4 Comments
Dec 3, 2022Liked by Michael Huemer

I was thinking about PC, and I'm wondering if "no grounds for doubting" is too strong of a condition. I think PC is reasonable and that appearances should be presumed true, but it always seems like I can provide SOME grounds for doubting beliefs about the external world.

I read your brain in a vat paper a while ago. I think it makes sense to be skeptical of that, but Bostrom's simulation argument provides some reason to think that the simulation would have a sort of coherent nature. I don't believe that I'm in a simulation but I do think that Bostrom's argument is at least possible and so I think that (3) "The fraction of all people with our kind of experiences that are living in a simulation is very close to one" is maybe true. I don't find it likely, but maybe there is a 0.1% chance. Isn't this grounds for doubting? If I assigned 10%, is that? Something like 90% must surely count.

This wouldn't be grounds for doubting my intellectual impressions, like 2+2 = 4. But maybe this is grounds for doubting the actual existence of external objects. I think that even if I say there is a .1% chance I'm in a simulation, I still have justified beliefs about the external world. So, I'm wondering if "no grounds" is too strict.

Anyway, thanks for the article.

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Well, the strength of the grounds for doubt would be proportional to how much they reduce the initial justification for your belief. Only very strong grounds would completely eliminate your justification.

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Hey Dr. Huemer, are you still doing your QnA post? I'm thinking about subscribing and want to know if you plan on responding to that same post or are going to create a new one later. https://fakenous.substack.com/p/ask-me-anything

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Agreed. This needs to become a regular thing.

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