tag:blogger.com,1999:blog-3891434218564545511.post4272426507004359273..comments2024-03-28T13:23:50.623-05:00Comments on Alexander Pruss's Blog: "Why are you telling me this?" and protocolsAlexander R Prusshttp://www.blogger.com/profile/05989277655934827117noreply@blogger.comBlogger6125tag:blogger.com,1999:blog-3891434218564545511.post-42361119567144790462016-01-27T09:50:39.072-06:002016-01-27T09:50:39.072-06:00Maybe the simplest thing to say is this. When a sp...Maybe the simplest thing to say is this. When a speaker informs you of something, you need to update not just on the content of what was said, but also on the fact that the speaker informed you of it. And lots of stuff can be learned from the latter fact.Alexander R Prusshttps://www.blogger.com/profile/05989277655934827117noreply@blogger.comtag:blogger.com,1999:blog-3891434218564545511.post-69920620871794555432016-01-26T22:23:09.372-06:002016-01-26T22:23:09.372-06:00Here is another way to state the point about proto...Here is another way to state the point about protocols: to apply Bayes, it’s not enough to know what actually happened. You also have to know, or make assumptions about, all the relevant alternatives that might have happened. In fancy language, you are conditioning relative to an express or implied partition.<br /><br />Example: a friend rolls a die and tells you that the outcome is even. What is the chance that it is 2? The obvious answer is 1/3. This is based on the implied partition {even, odd}. But maybe your friend had instructions say “even” iff the outcome was 2, and otherwise to say nothing. It is easy to make up variations.<br /><br />In real life, it’s unusual to have the required knowledge.IanShttps://www.blogger.com/profile/00111583711680190175noreply@blogger.comtag:blogger.com,1999:blog-3891434218564545511.post-69630382226742947992016-01-26T11:06:46.117-06:002016-01-26T11:06:46.117-06:00Testimony may be particularly special. :-) A testi...Testimony may be particularly special. :-) A testifier often testifies in order to produce a particular effect in you. In most other interactions in the world, the world doesn't care what you make of it.Alexander R Prusshttps://www.blogger.com/profile/05989277655934827117noreply@blogger.comtag:blogger.com,1999:blog-3891434218564545511.post-90139315301951060302016-01-26T09:07:51.654-06:002016-01-26T09:07:51.654-06:00Another way to put this might be that the evidenti...Another way to put this might be that the evidentialists' picture of evidence that is just "there", given, is often misleading. Rather than an investigator finding evidence, frequently the evidence finds the investigator. (Especially in cases of testimony.) And then one has to worry about selection effects in the evidence: why did just _this_ evidence come find me just _now_? Heath Whitehttps://www.blogger.com/profile/13535886546816778688noreply@blogger.comtag:blogger.com,1999:blog-3891434218564545511.post-80221126944721008842016-01-25T14:16:52.628-06:002016-01-25T14:16:52.628-06:00Even if it's just a coincidence, we can learn ...Even if it's just a coincidence, we can learn from it.Alexander R Prusshttps://www.blogger.com/profile/05989277655934827117noreply@blogger.comtag:blogger.com,1999:blog-3891434218564545511.post-36193395872869835902016-01-25T13:49:56.833-06:002016-01-25T13:49:56.833-06:00" But if you tell me that you were telling me..." But if you tell me that you were telling me this because you decided, before finding out whether p was true, that you were going to tell me whether or not the disjunction is true, then my near-certainty that I have hands should be shaken."<br /><br />A better question would be "what is the causal connection between the facts of your stated disjunction"? Without a known causal connection, there could still just have been a coincidence making the statement true, and the truthful person could have just successfully found such a coincidence on purpose.<br /><br />If I say I have no hands when pigs fly, making pigs fly won't remove my hands.<br />Williamhttps://www.blogger.com/profile/12533263841520213358noreply@blogger.com