I reckon I can make it, and it'll be my first in Sydney. Looking forward to it!

I reckon I can make that!

Once again, the problem isn't "How do I ignore rules and go with my gut?", it's "What do I do when my gut says 'Search me'?". So your answer isn't so much "random until satisficing by intuitive standards", and more like "random". Which is dominated by rules if rules exist, and the current best candidate if they don't.

I argued earlier that the only circumstances under which it should be morally acceptable to impose a particular way of thinking on children, is when the result will be that later in life they come to hold beliefs that they would have chosen anyway, no matter what alternative beliefs they were exposed to. And what I am now saying is that science is the one way of thinking — maybe the only one — that passes this test. There is a fundamental asymmetry between science and everything else.

• Nicholas Humphrey, What Shall We Tell the Children?

Please post anything there might be on how to deal with that. I'm exactly like that, and my rules often break down and then I'm unable to decide.

I've known someone else like that. She made rules about food because it made it easier to decide what to eat.

Could you also post the cites on why "obsessive-compulsive"? Neither I nor the other person have an OCD diagnosis or seem to match the criteria. Any OCD LWers want to chip in?

Harry tested whether you could make something weird happen by drinking the tea, not whether you could make someone drink the tea when you did something weird, subject to you not yourself knowing what would be weird enough before you saw them drinking.

I have refined my idea based on some re-reading. I forgot that you aren't guaranteed to choke on every sip. Someone let me know if the following is too farfetched.

As you said, when something shocking is going to happen, someone with access to the tea feels an impulse to drink it. Now recall this line from chapter 7, not given much thought to by Harry:

"It doesn't always happen immediately," the vendor said. "But it's guaranteed to happen once per can, or your money back."

So translating to the backwards-causation hypothesis, if nothing shocking is going to happen before you finish drinking the can, the tea stops you drinking it.

OK, let's put this together with the idea that time-reversed causation preserves self-consistency. I deduce that if you sit someone down in front of a glass of Comed-Tea for lunch they will start drinking from it only if they will be shocked enough to choke on it at some point. So what you do is resolve to take the 'water' away if your lunch-mate drinks from it and does not splutter. The Comed-Tea enchantment, by self-consistency, will ensure that this never actually happens, so you can now be certain that if your buddy raises his glass and starts to sip, he will choke.

Now you do what I suggested and run through your guesses. If your buddy raises his glass, you know that what you're about to say will be shocking. If he doesn't, you don't bother saying it. We know that Comed-Tea creates a strong impulse to drink it when one is about to be shocked, so your buddy, not knowing what he's drinking, is a sure bet to drink it if he is in fact about to be shocked. The only part of my idea that is now in question is this: if your resolve to do something shocking is conditional only on him drinking the tea, and his drinking the tea is conditional only on your being about to do something shocking, will he drink the tea in response to your commitment, given that your possible action is in fact shocking?

A causes B; B causes A. Do A and B both occur, or do neither? That's exactly the same question that occurs to Harry when he gets the Time-Turner. And that in turn makes me think that I'm missing something, because it can't be the case that all temporally self-consistent A-B pairs happen. Any ideas?

Since some people have opined that maybe we're not alone in the universe, I'll write down the strongest argument in that I can think of in favor of this position. (To win, you must fight not only the creature you encounter; you must fight the most horrible thing that can be constructed from its corpse. )

The strongest reason that aliens might be invisible to us is that they are deliberately hiding. In fact I think that this is the only plausible reason.

Why would they be hiding? Well, they might be frightened that they're in a simulation, and that the simulators have some crude algorithms that search massive tracts of space (many, many hubble volumes in size) by simply looking for inhomogeneity on the galaxy or supercluster level. The advanced aliens don't want to get caught by the simulator.

This explanation would still work even if we're not in a simulation: the threat of it is enough. Even a small probability that we're in a simulation given the intelligence and data that an advanced alien civilization would have might be enough to offset the (perhaps small?) advantages of expansion, especially given recent work on bounded utility functions.

EDIT: This could be combined with the singularity hypothesis: perhaps all superintelligences, convergently decide not to expand.

Or perhaps it would be perfectly reasonable to relax the requirement that units of measurement be as objective as they are in practice. If Helen of Troy was N standards of deviation above the norm in beauty (trivia: N is about 6), we can declare the helen equal to N standards of deviation in beauty, and then agents capable of having an impression of beauty could look at random samples of people and say how beautiful they are in millihelens.

That's still creating a unit of measurement, it just uses protocols that prime it with respect to one person rather than a physical object. It doesn't require a concept of fractional truth, just regular old measurement, probability andinterpolation.

Why don't you spend some time more precisely developing the formalism... oh, wait

how can this be treated formally? I say, to heck with it.

That's why.

Re. the linked article about the cognitive confusion test:

80 percent of high-scoring men would pick a 15 percent chance of $1 million over a sure $500, compared with only 38 percent of high-scoring women, 40 percent of low-scoring men and 25 percent of low-scoring women.

Wow. That's the most mind-blowing thing I've read in a while. I can't think of a good explanation for anyone picking the $500, let alone the male-female difference. Maybe they assume that someone might actually give them $500, but the $1M is a scam. And how does this square with the idea that poor people play the lottery more?

Princeton students scored a mean of 1.63. Heh.

1. Some paranormal phenomena such as ghost sightings and communication with the dead are actually real, though only able to be perceived by people with a particular sensitivity.

2. My life has been a protracted hallucination.

3. One or more gods exist and play an active part in our day-to-day lives.

4. A previous civilisation developed advanced enough technology to leave the planet and remove all traces of their existence from it.

I would not believe that rationality has no inherent value - that belief without evidence is a virtue.