Okay, this is going to sound weird. But again, how do I know that getting vaccinated doesn’t change a person’s sexual orientation? Presumably, the drug was tested, and someone would have noticed if the intervention group turned out “less straight” than the controls. But that doesn’t rule out the possibility that something about me choosing to have my child vaccinated will make him/her non-heterosexual. To us, this just contradicts common sense about how the world works, but that common sense isn’t represented anywhere in the problem as you stated it.
If all I know about the universe I inhabit are the conditional probabilities you gave, then no, I wouldn’t have my child vaccinated. In fact, I would even have to precommit to not having my child vaccinated, in the case that I find out his/her sexual orientation later. On the face of it, this conclusion isn’t any more ridiculous than Prisoner’s dilemma, where you should defect if your opponent defects, and defect if your opponent cooperates, but should cooperate if you don’t know what your opponent will do. Even though your opponent will either cooperate or defect.
UDT solves the apparent contradiction by saying that you should cooperate even if you know what your opponent will choose (as long as you think your opponent is enough like you that you would have predicted his decision to correlate with your own, had you not already known his decision). But this also leads to an intuitively absurd conclusion: that you should care about all worlds that could have been the same way you care about your own world. Sacrificing your own universe for the sake of a universe that could have been may be ethical, in the very broadest sense of altruism, but it doesn’t seem rational.
Okay, this is going to sound weird. But again, how do I know that getting vaccinated doesn’t change a person’s sexual orientation? Presumably, the drug was tested, and someone would have noticed if the intervention group turned out “less straight” than the controls. But that doesn’t rule out the possibility that something about me choosing to have my child vaccinated will make him/her non-heterosexual. To us, this just contradicts common sense about how the world works, but that common sense isn’t represented anywhere in the problem as you stated it.
If all I know about the universe I inhabit are the conditional probabilities you gave, then no, I wouldn’t have my child vaccinated. In fact, I would even have to precommit to not having my child vaccinated, in the case that I find out his/her sexual orientation later. On the face of it, this conclusion isn’t any more ridiculous than Prisoner’s dilemma, where you should defect if your opponent defects, and defect if your opponent cooperates, but should cooperate if you don’t know what your opponent will do. Even though your opponent will either cooperate or defect.
UDT solves the apparent contradiction by saying that you should cooperate even if you know what your opponent will choose (as long as you think your opponent is enough like you that you would have predicted his decision to correlate with your own, had you not already known his decision). But this also leads to an intuitively absurd conclusion: that you should care about all worlds that could have been the same way you care about your own world. Sacrificing your own universe for the sake of a universe that could have been may be ethical, in the very broadest sense of altruism, but it doesn’t seem rational.
In this case, it’s because I said so. ;)
We could imagine another study where this was observed.