Re: This 'n' that
Posted: Wed Apr 04, 2018 1:11 pm
I don't really think the original result (observing the red dress provides confirmation that all ravens are black) is a paradox. Instead, I think it shows that humans are really, really bad at intuitively grasping the implications of very large numbers. If I have seen one black raven and was able to observe every non-black thing in the universe, then of course I would confirm that all ravens are black. The problem is that the set of non-black things in the universe is uncountably large, so I don't really learn much by any particular observation.
Your idea of defining an observational universe helps a lot with this problem. Let's say I'm sitting down to play a game of go, and my opponent hands me a bowl that is (apparently) filled with black stones. My working hypothesis is that "All go stones in this bowl are black." Making observations outside of the bowl doesn't add to my knowledge about the situation. But if I catch a glimpse of white in the bowl, only to realize that an errant piece of paper had fallen inside, it does add (some) information to support my hypothesis. Of course, you're right that it's weak evidence. I won't know for sure that there are no white stones buried in the bowl until I have examined every stone in the bowl.
The use of a statistical epistemology makes more sense in this limited universe, too. If I know there are only 180 go stones in the bowl and I have observed 179 of them to be black, that would increase my confidence in the hypothesis that all of the stones are black. Contrast this putting my hand into a bowl and pulling out a single stone at random: that doesn't tell me a whole lot about the makeup of the bowl. (Unless, of course, I allow my previous knowledge that go players tend to keep their stones separated by color to inform my hypothesis.
)
By the way, Hempel's basic hypothesis was wrong: there are (rarely) white ravens.
Also, I found a really great guide to Bayes rule and its implications. The final page on the path I followed was on Bayesian scientific virtues, and I think it sheds light on why so many people feel uncomfortable with the Carlos decision. I don't have time to outline all of that right now (and this thread probably isn't the place), but at the very least there was not testing of the advance prediction that similarity to Leela's top three moves would be highly correlated with cheating.
Your idea of defining an observational universe helps a lot with this problem. Let's say I'm sitting down to play a game of go, and my opponent hands me a bowl that is (apparently) filled with black stones. My working hypothesis is that "All go stones in this bowl are black." Making observations outside of the bowl doesn't add to my knowledge about the situation. But if I catch a glimpse of white in the bowl, only to realize that an errant piece of paper had fallen inside, it does add (some) information to support my hypothesis. Of course, you're right that it's weak evidence. I won't know for sure that there are no white stones buried in the bowl until I have examined every stone in the bowl.
The use of a statistical epistemology makes more sense in this limited universe, too. If I know there are only 180 go stones in the bowl and I have observed 179 of them to be black, that would increase my confidence in the hypothesis that all of the stones are black. Contrast this putting my hand into a bowl and pulling out a single stone at random: that doesn't tell me a whole lot about the makeup of the bowl. (Unless, of course, I allow my previous knowledge that go players tend to keep their stones separated by color to inform my hypothesis.
By the way, Hempel's basic hypothesis was wrong: there are (rarely) white ravens.
Also, I found a really great guide to Bayes rule and its implications. The final page on the path I followed was on Bayesian scientific virtues, and I think it sheds light on why so many people feel uncomfortable with the Carlos decision. I don't have time to outline all of that right now (and this thread probably isn't the place), but at the very least there was not testing of the advance prediction that similarity to Leela's top three moves would be highly correlated with cheating.