Andrew: I favor Bryan Caplan’s explanation: when a belief you hold starts to have material consequences for you, when before it did not, your brain switches to more “realistic” thinking. From introspection, I find this to be true. It’s a great experiment you can do on yourself anytime. Think about something you believe strongly, and then consider taking an offer to put money on it. In my experience—and I’m the only one I can observe for this—I get a weird feeling, like a complete perception shift. (If I studied psychology, I might toss in a “Gestalt” somewhere.)
Eliezer_Yudkowsy is right: If you really believe something will happen, and you like money, and betting that it will happen will get you more money, that implies that you should make the bet. (Issues about the bookie can be resolved by having a friend secure the bet.) The refusal to bet therefore suggests the person is being dishonest about his stated level of certainty. I believe Robin_Hanson has made a good point before about how claims like “Oh, Hillary can’t win, I know it” shouldn’t be read as actual claims of knowledge, but a “signal” about whose “team” you are on, and therefore asking to bet misses the real point of that person in making that statement.
Andrew: I favor Bryan Caplan’s explanation: when a belief you hold starts to have material consequences for you, when before it did not, your brain switches to more “realistic” thinking. From introspection, I find this to be true. It’s a great experiment you can do on yourself anytime. Think about something you believe strongly, and then consider taking an offer to put money on it. In my experience—and I’m the only one I can observe for this—I get a weird feeling, like a complete perception shift. (If I studied psychology, I might toss in a “Gestalt” somewhere.)
Eliezer_Yudkowsy is right: If you really believe something will happen, and you like money, and betting that it will happen will get you more money, that implies that you should make the bet. (Issues about the bookie can be resolved by having a friend secure the bet.) The refusal to bet therefore suggests the person is being dishonest about his stated level of certainty. I believe Robin_Hanson has made a good point before about how claims like “Oh, Hillary can’t win, I know it” shouldn’t be read as actual claims of knowledge, but a “signal” about whose “team” you are on, and therefore asking to bet misses the real point of that person in making that statement.