The way people interpret the data in favor of one side or the other has more to do with the basic assumptions under which they operate. I want to write an article about this.
So if you are one who generally distrusts the government like most libertarians you will find it easy to see a conspiracy. If you generally trust the government you will tend to dismiss any conspiracy.
One question you have to ask yourself in this specific context is: what do you think about secret services in general(not only the american ones), what is their mission? Once you understand that they are not there to protect the people or democracy but to advance the geopolitical interests of their respective nations you are set.
In the art of rationality there is a discipline of closeness-to-the-issue—trying to observe evidence that is as near to the original question as possible, so that it screens off as many other arguments as possible.
The question in this case is: “Were explosives planted in WTC7?”.
Surely the question is “What caused WTC7 to collapse”—we would have no cause to ask about explosives if it hadn’t collapsed?
It is known with great confidence that two commercial airliners with tanks full of jet fuel crashed into nearby buildings six hours earlier, causing their total collapse. That’s an unlikely enough event. The conjunction of two airliners crashed into nearby buildings AND planted explosives is by necessity less likely.
Roland, you seem to be missing the point here. He’s making two of them. One, asking about explosives is in some way privileging the hypothesis. Second, the probability of A and B must be at most the probability of A and B together. Your response has nothing to do with either of these issues.
One I have answered at least twice before, I’m getting tired of reiterating it again and again.
Second my point was to screen off arguments by getting close to the issue. So the conjunction with other events is irrelevant, but even if it weren’t, you are assuming that the events are independent, what if they aren’t?
So the conjunction with other events is irrelevant, but even if it were, you are
assuming that the events are independent, what if they aren’t?
No. Even if probabilities are not independent, the probability of both happening is still less than the probability of either one happening. This should be intuitively obvious, but since it apparently isn’t, here’s the math:
P(A v B)= P(A) + P(B) - P(A^B). So P(A^B) = P(A) + P(B) - P(A v B). Since P(A v B) >= P(A) and P(A v B) >= P(B) we have that P(A^B) ⇐ min(P(A),P(B)).
A more salient point here might be that the conjunctive issue doesn’t matter much because the probability that planes did crash into the Twin Towers is so high that it is almost 1 (unless anyone here thinks that the planes were actually holograms disguising a missile http://www.youtube.com/watch?v=q5NNh6WnVZo )), and thus the conjunction argument doesn’t by itself substantially reduce the probability of explosives being planted in WTC7. This sort of conjunction argument only works when both aspects of the conjunction have a probability substantially lower than 1.
You are not just confused about basic probability. You also seem to be confused about what Eliezer is talking about when he discusses closing off arguments. Please read his example again with the Wright Brothers. He’s talking about closing off classes of arguments as of much lower relevance to estimating an expectation. Thus, physics arguments are better in a general sense than arguments from authority. And physical demonstrations in many conditions are better in a general sense than arguments from the laws of physics. This is not at all the same as closing off questions about what connected events occurred (such as questions of motivation or the nature of the crashing planes or the like). It may help to reread that sequence.
Yes his point is more general than physics but that’s not the point! He’s not closing off explanations of related issues in reality. He’s closing off methods of weak evidence. He’s closing off classes of evidence, not evaluations of expected probabilities. Maybe expanding his example will make this more clear: If his example were equivalent to yours, instead of closing off Kelvin’s opinion, you’d be closing off whether or not the Wright Brothers had built an air tunnel. See the difference?
I assume that by “secret services” he was referring to the CIA (known for covert ops and espionage), rather than the agency called the Secret Service (known for its presidential bodyguards).
Secret services in general all over the world: Russian FSB, british MI6, CIA, NSA, etc…
I mean it in the sense of wikipedia: Secret service, umbrella term for various kinds of police or intelligence organizations
http://en.wikipedia.org/wiki/Secret_Service_(disambiguation)
That’s a rather loose association of organizations there, as they each have a very different mission (although MI6 & CIA are mostly on the same page for each respective country). The NSA, though, is mostly just about crypto and hiding things, where the others are usually more concerned with finding things.
They are a sort of necessary evil that really needs some newer controls for their operations in this day and age.
The way people interpret the data in favor of one side or the other has more to do with the basic assumptions under which they operate. I want to write an article about this.
So if you are one who generally distrusts the government like most libertarians you will find it easy to see a conspiracy. If you generally trust the government you will tend to dismiss any conspiracy.
One question you have to ask yourself in this specific context is: what do you think about secret services in general(not only the american ones), what is their mission? Once you understand that they are not there to protect the people or democracy but to advance the geopolitical interests of their respective nations you are set.
Redirecting discussion from here.
Surely the question is “What caused WTC7 to collapse”—we would have no cause to ask about explosives if it hadn’t collapsed?
It is known with great confidence that two commercial airliners with tanks full of jet fuel crashed into nearby buildings six hours earlier, causing their total collapse. That’s an unlikely enough event. The conjunction of two airliners crashed into nearby buildings AND planted explosives is by necessity less likely.
In the art of rationality there is a discipline of closeness-to-the-issue—trying to observe evidence that is as near to the original question as possible, so that it screens off as many other arguments as possible.
Roland, you seem to be missing the point here. He’s making two of them. One, asking about explosives is in some way privileging the hypothesis. Second, the probability of A and B must be at most the probability of A and B together. Your response has nothing to do with either of these issues.
One I have answered at least twice before, I’m getting tired of reiterating it again and again. Second my point was to screen off arguments by getting close to the issue. So the conjunction with other events is irrelevant, but even if it weren’t, you are assuming that the events are independent, what if they aren’t?
No. Even if probabilities are not independent, the probability of both happening is still less than the probability of either one happening. This should be intuitively obvious, but since it apparently isn’t, here’s the math:
P(A v B)= P(A) + P(B) - P(A^B). So P(A^B) = P(A) + P(B) - P(A v B). Since P(A v B) >= P(A) and P(A v B) >= P(B) we have that P(A^B) ⇐ min(P(A),P(B)).
A more salient point here might be that the conjunctive issue doesn’t matter much because the probability that planes did crash into the Twin Towers is so high that it is almost 1 (unless anyone here thinks that the planes were actually holograms disguising a missile http://www.youtube.com/watch?v=q5NNh6WnVZo )), and thus the conjunction argument doesn’t by itself substantially reduce the probability of explosives being planted in WTC7. This sort of conjunction argument only works when both aspects of the conjunction have a probability substantially lower than 1.
You are not just confused about basic probability. You also seem to be confused about what Eliezer is talking about when he discusses closing off arguments. Please read his example again with the Wright Brothers. He’s talking about closing off classes of arguments as of much lower relevance to estimating an expectation. Thus, physics arguments are better in a general sense than arguments from authority. And physical demonstrations in many conditions are better in a general sense than arguments from the laws of physics. This is not at all the same as closing off questions about what connected events occurred (such as questions of motivation or the nature of the crashing planes or the like). It may help to reread that sequence.
(Edits for grammar and punctuation)
I read the Eliezer’s post before commenting. Yes, he has some specific examples using physics, etc… but his point is general.
Yes his point is more general than physics but that’s not the point! He’s not closing off explanations of related issues in reality. He’s closing off methods of weak evidence. He’s closing off classes of evidence, not evaluations of expected probabilities. Maybe expanding his example will make this more clear: If his example were equivalent to yours, instead of closing off Kelvin’s opinion, you’d be closing off whether or not the Wright Brothers had built an air tunnel. See the difference?
Seeing a conspiracy requires a distrust of the government AND an astoundingly high opinion of their competence.
Are you implying that this is a contradiction?
Not a contradiction, but they are two distinct claims. Whether the government is untrustworthy and whether it’s competent are separate arguments.
Most libertarian criticisms of the government that i’ve heard have focused on arguments that the government is inefficient and incompetent.
What are you talking about with the Secret Services?
I don’t understand your question.
In the original comment to which I responded, you make a query about “what do you think about secret services in general, what is their mission?”
Where you referring to THE Secret Service… Or to more general services of some sort that also happen to be secret?
I assume that by “secret services” he was referring to the CIA (known for covert ops and espionage), rather than the agency called the Secret Service (known for its presidential bodyguards).
Secret services in general all over the world: Russian FSB, british MI6, CIA, NSA, etc… I mean it in the sense of wikipedia: Secret service, umbrella term for various kinds of police or intelligence organizations http://en.wikipedia.org/wiki/Secret_Service_(disambiguation)
That’s a rather loose association of organizations there, as they each have a very different mission (although MI6 & CIA are mostly on the same page for each respective country). The NSA, though, is mostly just about crypto and hiding things, where the others are usually more concerned with finding things.
They are a sort of necessary evil that really needs some newer controls for their operations in this day and age.
BTW, here is a handy graphic representing the relation between the various U.S. intelligence agencies.