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Comment author: TruePath 29 March 2017 05:09:29PM 1 point [-]

I worry such a plan will face significant legal hurdles. As suggested the building would probably not fall into the exceptions to the federal fair housing act (is that right) for choosing roommates (it's not a single family dwelling but a group of apartments in some sense).

But you EXACTLY want to choose who lives there based on political/religious beliefs (almost by definition it's impossible to be a rationalist and a dogmatic unquestioning conservative christian). Also by aspects of family makeup in that you don't want people living in this community to import a large extended family to live with them if that family doesn't share the values/concerns of the other people living in the community.

Basically, I think the degree of control you want over who lives in the building may be incompatible with various non-discrimination laws. However, one could probably find 20 families that could jointly purchase the building as condos to avoid this problem.

But I don't see any way around these problems in the long run. As the original group breaks up it will be hard to replace them without legally problematic screening.

In response to Say It Loud
Comment author: TruePath 14 February 2016 07:50:57PM 0 points [-]

Sorry, but you can't get around the fact that humans are not well equipped to compute probabilities. We can't even state what our priors are in any reasonable sense much less compute exact probabilities.

As a result using probabilities has come to be associated with having some kind of model. If you've never studied the question and are asked how likely you think it is there are intelligent aliens you say something like "I think it's quite likely". You only answer with a number if you've broken it down into a model (chance life evolves * average time to evolve intelligencechance of disaster..).

Thus, saying something like "70% chance" indicates to most people that you are claiming your knowledge is the result of some kind of detailed computation and can thus be seen as an attempt to claim authority. You can't change this rule on your own.

Thankfully, there are easy verbal alternatives. "Ehh, I guess I would give 3:1 odds on it" and many others. But use of chance/probability language isn't it.

Comment author: TruePath 11 October 2015 09:56:34PM 1 point [-]

Uhh, why not just accept that you aren't and can never be perfectly rational and use those facts in positive ways.

Bubbles are psychologically comforting and help generate communities. Rationalist bubbling (which ironically includes the idea that they don't bubble) probably does more to build the community and correct other wrong beliefs than almost anything else.

Until and unless rationalist take over society the best strategy is probably just to push for a bubble that actively encourages breaking other (non-rationalist) bubbles.

Comment author: Fluttershy 12 November 2014 06:12:03AM *  2 points [-]

This error has been corrected; thank you for pointing this out!

I actually did a bit more research, and it really seems like flu vaccine efficacy in healthy adults is more like 70% (and sometimes as high as 90%), despite the fact that the average efficacy of the vaccine throughout the population is around 60%. The reason that efficacy in healthy adults is so high, relative to the average efficacy, is that efficacy in the elderly is around 30-40%.

Also, note that about 42% of the US population gets flu shots on any given year. So, if 10% of people on average get the flu, and the vaccine is 60% efficacious throughout the population, then we can write the following equations, defining sick1 as the event in which a person who was vaccinated gets the flu, and sick2 as the event in which a person who was not vaccinated gets the flu:

p(sick1) x 0.42 + p(sick2) x 0.58 = 1 x 0.10

p(sick1) = p(sick2) x 0.60

Solving this system of equations, we get:

p(sick1) = 0.0721

p(sick2) = 0.120 (previous typo: had been written as 0.0120)

The practical implication of this is that the conservative analysis conducted in this report, and shown in Figure 1, assumes that around 5.7% (rather than a more realistic 10 or 12%) of the population will catch the flu in any given year.

Comment author: TruePath 14 November 2014 10:35:23PM *  0 points [-]

So the equations should be (definition of vaccine efficacy from wikipedia)

.6 * p(sick2) = p(sick2) - p(sick1)
p(sick1) - .4 p(sick2) = 0 . i.e. efficacy is the difference be the unvaccinated and vacinated rates of infection divided by the unvaccinated rate. You have to assume there is no selective pressure in terms of who gets the vaccine (they have the same risk pool as the normal population for flu which is surely untrue) to get your assumtion that

.42* p(sick1) + .58*p(sick2) = .1 p(sick1) + 1.38p(sick2) = .238

or 1.78 p(sick2) = .238

p(sick2)=.13 (weird I getting a different result) p(sick1) = .05

Did I solve wrong or did you. I do math so I can't actually manipulate numbers very well but I not seeing the mistake.

Comment author: dspeyer 11 November 2014 08:18:00AM 10 points [-]

Omitting death seems like a big deal. Very crudely, it looks like p=10^-4. It's said that society values each life at $5M, so that's E=-$500 already, but each individual likely values their own life a bit higher.

Comment author: TruePath 14 November 2014 10:12:34PM 1 point [-]

Not with respect to their revealed preferences for working in high risk jobs I understand. There are a bunch of economic papers on this but it was a surprisingly low number.

Comment author: TruePath 14 November 2014 08:01:20PM 0 points [-]

Well it can't still be instrumental rationality anymore. I mean suppose the value being minimized is overall suffering and you are offered a (non-zero probability one time...and you know there are no other possible infinitary outcomes) threat that if you don't believe some false claim X god will create an infinite (no other infinite outcomes) amount of suffering. You know before the choice to believe the false claim that no effect of believing it will increase expected suffering to overwhelm the harm of not believing it.

But the real rub is what do you say about the situation where the rocks turn out to be rocks cleverly disguised as people. You still have every indication that your behavior convincing yourself is an attempt to believe a false statement but it is actually true.

Does the decision procedure which says whatever you want it to normally say but makes a special exception that you can deceive yourself if (description of this situation which happens to identify it uniquely in the world).

In other words is it a relation to truth that you demand. In which case the rule gets better whenever you make exceptions that happen (no matter how unlikely it is) in the actual world to generate true and instrumentally useful beliefs. Or is it some notion of approaching evidence?

If the latter you seem to be committed to the existence of something like Carnap's logical probability, i.e., something deducible from pure reason that assigns priors to all possible theories of the world. This is a notoriously unsolvable (in the sense that it doesn't have one) unsolvable problem.

At the very least can you state some formal conditions that constrain a rule for deciding between actions (or however you want to model it) that captures the constraint you want?

In response to 9/26 is Petrov Day
Comment author: CarlShulman 26 September 2007 07:06:36PM 7 points [-]

"I'm tempted to donate, to honor his deed." Presumably he has received some cash from the documentary, but the incentives created by his later life (and its publication) are horribly perverse.

It seems that this is right up the alley of the Nuclear Threat Initiative, which is supported by Warren Buffett and other donors. http://en.wikipedia.org/wiki/Nuclear_Threat_Initiative You could write a letter to them discussing the incentives and suggesting a prize for averting mega-disasters or existential risk, nominating Petrov for the first award.

Comment author: TruePath 14 November 2014 12:29:42PM 1 point [-]

Given that he would be dead otherwise (and the strong human survival drive) I don't see how the incentives are perverse.

I mean to make the incentives positive for pushing the button requires some really strong conditioning or torture threats.

Utilitarianism and Relativity Realism

-3 TruePath 23 June 2014 07:12PM



Most people on less wrong seem to be some kind of hedonic consequentialist.   They think states with less suffering and more joy are better.  Moreover, it is intuitive that if you can cause some improvement in human well-being to be achieved then (other things being equal) it is better to realize that improvement as soon as possible.  Also, most people on this site seem to be realists about special relativity.  That is they assume that any inertial reference frame is an equally valid point from which to describe reality rather than believing there is one true reference which offers a preferred description of reality.  I will point out that these beliefs (plus some innocuous assumptions) lead quickly to paradox.

Relativity Realism

Before I continue I want to point out that empirical observations really are agnostic about the existence of a preferred reference frame.  Indeed, it's a consequence of the theory of relativity itself that it's predictions are equally well explained by postulating a single true inertial reference frame and simply using the Lorentz contraction and time dilation equations to compute behavior for all moving objects.  To see that this must be true not that if we take relativity seriously the laws of physics must work correctly in any reference frame.  In particular, if we imagine designating one reference frame to be the true reference frame then, relativity itself, tells us that applying the laws of physics in that reference frame has to give us the correct results.  

In other words once we accept Einstein's equations for length contraction and time dilation with velocity we can interpret those equations as either undermining the idea of a fixed ether against which objects move (any reference frame is equally valid) or that there really is a fixed ether but objects in motion behave in such a manner that we can't empirically distinguish what is at rest.

At first blush this second result seems so jury rigged that surely the simpler assumption is that there is no preferred reference frame.  This relies on a false description of the situation.  The question isn't, "do we assign a low prior probability to the laws of physics conspiring to hide the true rest frame from us?"  Presumably we do.  The question should be, "given that the laws of physics do conspire to make a special rest frame empirically indistinguishable from any other inertial frames what probability do we assign to such a frame existing?"  After all it is a mathematical truth that the time dilation and length contraction do perfectly conspire to prevent us from measuring motion relative to some true rest frame (if it existed) so in deciding whether to believe in a preferred rest frame we aren't deciding between laws that would and wouldn't hide such a frame from us.  We are only deciding whether, given we have such laws, whether we think such an undetectable true rest frame exists.

To make it even more plausible that there is some true rest frame I will remark (but not argue) that relativity is a pretty general phenomena that can be derived from any model that conserves momentum, where the forces obey the inverse square law and all propagate at a constant speed relative to some fixed background, matter is held together in equilibrium states of these forces and time is implicitly measured via the rate it takes these forces to propagate.  In other words if you have atoms held together by EM forces and the time it takes physical processes to happen is governed by the time it takes either forces or matter to cross certain distances then relativity comes for free.  So it isn't amazing that we might have a true prefered reference frame and yet it be impossible to experimentally determine that frame.

(As an aside this interpretation of relativity, fully consistent with all observables so far, makes for much better scifi since FTL travel doesn't allow anyone to go back in time). 

A Paradox Resulting From Relativity Realism

Suppose we have two different brain implants that will be implanted in two different conscious but coma bound individuals.  After a delay of 10 minutes after implantation the first device delivers an instantaneous burst of euphoria every second.  The other delivers an instantaneous burst of discomfort every second.  I assume we would all agree that (with sufficient additional assumptions) the world is a better place if we implant just a device of the euphoria inducing kind and a worse place if we just implant a device of the second kind.  So assume the devices are appropriately calibrated so that the effect of implanting both is neutral (or very very nearly so).  So far so good.

I think we can all agree that the world would be better off if we delayed implanting the discomforting device by 10 minutes (or equivalently implanted the pleasurable device 10 minutes earlier).  If you dispute this conclusion then you get absurd results if you even admit the possibility of a universe that exists forever as in such a universe it is no better to permanently increase human welfare now than to delay that increase by 10 minutes or 10 centuries.

Now assume that the two individuals receiving the transplants are actually on spaceships moving in opposite directions at high rates of speed and the implantation is done at the instant they pass by each other.  For simplicity we assume everyone else dies at this instant (or add an irrelevance of identical outcomes assumption and note that the two ships are moving at the same velocity relative to everyone else).  

From the reference frame of the individual who received the beneficial implant we can analyze the situation as follows.  Without loss of generality we can assume the ships are traveling at an appropriate speed so that for every second that pases in our reference frame only 1/2 a second passes on the other ship.  Thus in this reference frame the first experience of discomfort is delayed by 10 minutes and then only occurs every other second.  Now surely the world is no worse off because the discomfort occurs less frequently.  But ignoring the fact that the discomforting device fires less frequently this is exactly equivalent to implanting the desirable device 10 minutes before the undesirable one.  Thus, since implanting both in the same reference frame was neutral, it is actually favorable (better than not implanting them) to do so when the recipients are in fast moving reference frames moving in opposite directions.  Note the same result holds if we assume the device only creates discomfort or euphoria a single time with the minor assumption that if two worlds only differ in events before time t then what happens after time t is irrelevant to which one is preferable.

However, the same analysis done in the reference frame of the unpleasant implant gives the exact opposite conclusion.


Avoiding the Paradox

Perhaps one might try and avoid the paradox by insisting that no experience truly occurs instantaneously.  However, this is easily seen to be futile.

Assume that each device inflicts pleasure or discomfort for duration epsilon << 1 second.  If you assume that the total badness of the uncomfortable experience is somehow mediated by changes in neurochemistry or other physical properties you are lead to the assumption that even described from the reference frame of the desirable implant the experience of 2*epsilon seconds of discomfort by the time dilated individual is really no worse than the experience of epsilon seconds of discomfort would be for someone with that implant in your reference frame.  In other words when time is dilated the experience of pain per unit time is diluted.  This leads to the exact same result as above.

On the other hand if we really do increase the weight we give to pain experienced by those undergoing time dilation an even simpler set of implants leads to paradox.  These implants start working immediately, one generating a pleasant experience for 5 minutes the other an unpleasant experience for 5 minutes again calibrated so that installing both is overall neutral.  Now by assumption from the reference frame of the beneficial implant things are overall worse (the longer duration of discomfort experienced by the other individual is overall worse than someone in the same reference frame getting the undesirable implant) and vice versa from the other reference frame.

The use of instantaneous experiences was merely a way to simplify the example but irrelevant to the underlying inequalities.  Those inequalities are a result of the implicit time discounting forced by the assumption that other things being equal it is better for improvements to occur now rather than later combined with the fact that realism about relativity renders facts about simultaneity incoherent.

Personally, I think the only decent way of avoiding this paradox is to deny realism about relativity.  Sure, it's a radical move.  However, it's also a radical move to say it's not true that it's better to cure cancer now than in 10 centuries even if the human race will continue to exist forever.  Indeed, even if you don't assume literally infinite duration of effects even an unbounded potential length of effect with probabilities that decrease sufficiently slowly is equally problematic.


I've deliberately avoided phrasing this dilemma in terms of a formal paradox and listing the assumptions necessary to generate the paradox.  Partly this is laziness but it's also a desire to see how people are inclined to respond before I attempt to draw up formal conditions.  After all I ultimately want to capture common views in the assumptions and if I don't know what people's reactions are I can't pick the right assumptions.


Comment author: Normal_Anomaly 28 January 2012 02:11:47AM 8 points [-]

Would discovering that a wavefunction collapse postulate exists be evidence for simulation? A simulation that actually computed all Everett branches would demand exponentially more resources, so a simulator would be more likely to prune branches either randomly (true or pseudo-) or according to some criterion.

Comment author: TruePath 22 June 2014 01:00:37AM 1 point [-]

No since experientially we already know that we don't perceive the world as if all everett branches are computed.

In other words what is up for discovery is not 'not all everett branches are fully realized'....that's something from our apparent standpoint as belonging to a single such branch we could never actually know. All we could discover was that the collapse of the wavefunction is observable inside our world.

In other words nothing stops the aliens from simply not computing plenty of everett branches but leaving no trace in our observables to tell us that only one branch is actually real.

Comment author: thakil 28 January 2012 10:35:57AM 3 points [-]

One thing that confuses me about these discussions, and I'm very willing to be shown where my reasoning is wrong, is that there seems to be an implicit assumption that the simulators must follow any of the rules they've imposed upon us. If I simulate a universe powered by the energy generated by avacados, would the avacado beings try to spot an avacado limit, or an order to the avacados?

A simulator could have a completely different understanding as to how the universe works.

I would guess the argument against this is that why else would we be simulated if not to be a reflection of the universe above? I'm not sure I buy this, or necessarily assign a high probability to it.

Comment author: TruePath 22 June 2014 12:57:10AM 0 points [-]

I tried to avoid assuming this in the above discussion. You are correct that I do assume that the physics of the simulating world has two properties.

1) Effective physical computation (for the purposes of simulation) is the result of repeated essentially finite decisions. In other words the simulating world does not have access to a oracle that vastly aids in the computation of the simulated world. In other words they aren't simulating us by merely measuring when atoms decay in their world and that just happens to tell them data about a coherent lawlike physical reality.

I don't think this is so much an assumption as a definition of what it means to be simulated. If the description of our universe is embedded in the natural laws of the simulating universe we aren't so much a simulation as just a tiny part of the simulating universe.

2) I do assume that serial computation is more difficult to perform than serial computation, i.e., information can't be effectively transmitted infinitely fast in the simulating universe. Effectively is an important caveat there since even a world with an infinite speed of light would ultimately have to rely signals from sufficiently far off to avoid detection problems.

This is something that surely is plausible to be true. Maybe it isn't. THAT IS WHY I DON'T CLAIM THESE CONSIDERATIONS CAN EVER GIVE US A STRONG REASON TO BELIEVE WE AREN'T A SIMULATION. I do think they could give us strong reasons to believe we are.

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