[knightoffaith]

1. I observe that people do not base their actions on sensory experience do stupid things.

2. Therefore, true knowledge or justification comes only from sensory experience and empirical evidence.

All that I'm saying is that (2) does not logically follow from (1), no more than "Socrates is mortal" follows from "All men are mortal". There's something missing here, an additional premise, (like "Socrates is a man" in the Socrates example).

[lisper]

> true knowledge or justification comes only from sensory experience and empirical evidence

That's a straw man. It's not "only", it's "primarily". Sensory experience is necessary, not sufficient.

[knightoffaith]

Fine, fine, replace only with primarily, and reread the comment, that's not a crucial point.

[lisper]

OK, but if you make that change then 2 does follow from 1.

[knightoffaith]

OK, let's be completely, utterly, crystal clear about this.

1. I observe that people who do not base their actions on sensory experience do stupid things.

2. Therefore, true knowledge or justification comes primarily from sensory experience and empirical evidence.

You're telling me that 2 is a logical implication of 1? You're perfectly happy with the way I've framed this---there are no hidden premises or anything like that? 2 is a direct, logical implication of 1?

[lisper]

I am not "perfectly happy" with it, no. For starters, I don't think there actually are people who do not base their actions on sensory experiences. Evolution mitigates against that pretty strongly.

I would say that if someone doesn't base their actions on sensory experience (a very big if) then they will be totally unable to navigate reality. They will almost certainly injure themselves, possibly others, and likely even kill themselves and maybe take others down with them. It's so obvious and the consequences so severe that it would be unethical to actually conduct this experiment.

Also, 2 is not a logical implication of 1. One can never rule out the possibility that, say, all human behavior is controlled by evil demons. What I would say is that my version of 1 is very compelling evidence for 2, and one of the things that makes it compelling is that it is so obviously true that a sane person would never even contemplate it as anything other than a thought experiment.

BTW, would you have any interest in being a guest on a podcast?

[knightoffaith]

>Also, 2 is not a logical implication of 1. One can never rule out the possibility that, say, all human behavior is controlled by evil demons. What I would say is that my version of 1 is very compelling evidence for 2, and one of the things that makes it compelling is that it is so obviously true that a sane person would never even contemplate it as anything other than a thought experiment.

Oh good, ok - you see my confusion, I thought you were saying that it was a logical implication. I would still say that 2 isn't really grounded in 1 so much as it is self-evidently true. Like, if we're being controlled by evil demons, 1 isn't even relevant---the question is fundamentally whether sense-experience gives us true knowledge bar extenuating circumstances or not; I think the answer is yes, but not because we see that this belief is a useful belief, it's because 2 itself is intuitively true. I don't believe that my perception of me sitting on a chair is good grounds for the proposition that I really am sitting on a chair not because of a thought experiment about lacking that belief leading to injury---I believe it because it seems true itself. And I think this is the right solution in general for related issues, whether it's inductive inferences (I think they're rational), belief in causality, belief in the validity of sense-data, or any other typical issue for empiricism.

The "X is key for survival, so X must be true" way of thinking has never been appealing to me---this seems to miss the point of what it means for something to be true. Like, I don't believe in 1+1=2 because it's useful for economics, physics, math, or whatever---I think it's true independently of its utility. Similarly for other truths.

>podcast

I'd prefer to not publicize my real name and face, so no, unfortunately (unless you'd be OK with that; I'd be happy to chat if so).