An earlier post of mine reviewed the most credible evidence I have managed to find regarding seemingly anomalous UFOs. My aim in this post is to mostly set aside the purported UFO evidence and to instead explore whether we can justify placing an extremely low probability on the existence of near aliens, irrespective of the alleged UFO evidence. (By “near aliens”, I mean advanced aliens on or around Earth.)
Specifically, after getting some initial clarifications out of the way, I proceed to do the following:
I explore three potential justifications for a high level of confidence (>99.99 percent) regarding the absence of near aliens: (I) an extremely low prior, (II) technological impossibility, and (III) expectations about what we should observe conditional on advanced aliens being here.
I review various considerations that suggest that these potential justifications, while they each have some merit, are often overstated.
For example, in terms of what we should expect to observe conditional on advanced aliens having reached Earth, I argue that it might not look so different from what we in fact observe.
In particular, I argue that near aliens who are entirely silent or only occasionally visible are more plausible than commonly acknowledged. The motive of gathering information about the evolution of life on Earth makes strategic sense relative to a wide range of goals, and this info gain motive is not only compatible with a lack of clear visibility, but arguably predicts it.
I try to give some specific probability estimates — priors and likelihoods on the existence of near aliens — that seem reasonable to me in light of the foregoing considerations.
Based on these probability estimates, I present Bayesian updates of the probability of advanced aliens around Earth under different assumptions about our evidence.
I argue that, regardless of what we make of the purported UFO evidence, the probability of near aliens seems high enough to be relevant to many of our decisions, especially those relating to large-scale impact and risks.
Lastly, I consider the implications that a non-negligible probability of near aliens might have for our future decisions, including the possibility that our main influence on the future might be through our influence on near aliens.
I think you have to update against the UFO reports being veridical descriptions of real objects with those characteristics because of just how ludicrous the implied properties are. This paper says 5370 g as a reasonable upper bound on acceleration, implying with some assumptions about mass an effective thrust power on the order of 500 GW in something the size of a light aircraft, with no disturbance in the air either from the very high hypersonic wake and compressive heating or the enormous nuclear explosion sized bubble of plasmafied air that the exhaust and waste heat emissions something like this would produce.
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7514271/
At a minimum, to stay within the bounds of mechanics and thermodynamics, you’d need to be able to ignore airflow and air resistance entirely, have the ability to emit reaction mass in a completely non-interacting form, and the ability to emit waste energy in a completely non-interacting form as well.
To me, the dynamical characteristics being this crazy points far more towards some kind of observation error, so I don’t think we should treat them as any kind of real object with those properties until we can conclusively rule out basically all other error sources.
So even if the next best explanation is 100x worse at explaining the observations, I’d still believe it over a 5000g airflow-avoiding craft that expels invisible reaction mass and invisible waste heat while maneuvering. Maybe not 10,000x worse since it doesn’t outright contradict the laws of physics, but still the prior on this even being technically possible with any amount of progress is low, and my impression (just from watching debates back and forth on potential error sources) is that we can’t rule out every mundane explanation with that level of confidence.
Thanks for your comment. I basically agree, but I would stress two points.
First, I’d reiterate that the main conclusions of the post I shared do not rest on the claim that extraordinary UFOs are real. Even assuming that our observed evidence involves no truly remarkable UFOs whatsoever, a probability of >1 in 1,000 in near aliens still looks reasonable (e.g. in light of the info gain motive), and thus the possibility still seems (at least weakly) decision-relevant. Or so my line of argumentation suggests.
Second, while I agree that the wild abilities are a reason to update toward thinking that the reported UFOs are not real objects, I also think there are reasons that significantly dampen the magnitude of this update. First, there is the point that we should (arguably) not be highly confident about what kinds of abilities an advanced civilization that is millions of years ahead of us might possess. Second, there is the point that some of the incidents (including the famous 2004 Nimitz incident) involve not only radar tracking (as reported by Kevin Day in the Nimitz incident), but also eye-witness reports (e.g. by David Fravor and Alex Dietrich in the case of Nimitz), and advanced infrared camera (FLIR) footage (shot by Chad Underwood during Nimitz). That diversity of witnesses and sources of evidence seems difficult to square with the notion that the reported objects weren’t physically real (which, of course, isn’t to say that they definitely were real).
When taking these dampening considerations into account, it doesn’t seem to me that we have that strong reason to rule out that the reported objects could be physically real. (But again, the main arguments of the post I shared don’t hinge on any particular interpretation of UFO data.)
I think this almost perfectly describes my problem with these videos/accounts/sensor readings. The same thing that makes them better evidence of aliens also makes them less likely to be real evidence. The crazier the physical constraints, the more likely “if this is real, the explanation is extra-terrestrial” becomes, but the less likely “it is real” becomes. Evidence that significantly increases the probability of “this is real” without significantly decreasing the probability of “if this is real, the explanation is extra-terrestrial” seems necessary yet elusive.
The discussion of UAPs lately reminds me of the “How would Magnus Carlsen beat me at chess?” example that is popular in alignment these days. The still-unexplained phenomena that people will demand explanations for must be rare and hard to explain without a lot of good observations, or they wouldn’t still be unexplained.
It seems similar to assuming that dark matter must be far more mysterious than just a particle, because we have so much trouble confirming any explanation of it, despite the fact that its observed behavior tells us that it should be extremely hard to confirm for any methods available to us.
I think the fact that the accelerations are close to, but not, a complete violation of physics is the most interesting, but it depends on how likely you think it is that a non-extraterrestrial explanation for a rare phenomena would also not seem to violate those laws. Or how likely a non-extraterrestrial explanation might be to appear to violate the laws of physics before further investigation. I do think this actually would make me update a bit in favor of extra-terrestrials if I thought about it more.
I wish my thoughts on this were better formulated, but I’ve been avoidant of UAP stuff for a while because engaging with it usually left me very frustrated and annoyed, and I don’t think it’s something we are likely to make meaningful progress on.
I really enjoyed the article! But in the end, rather than persuading me that the odds of alien presence is higher than I thought, it has instead further persuaded me that bayesian estimates (as used in EA) are pretty much useless for this type of question, and are likely to lead people astray.
You give a prior of 1 in a hundred that aliens have a presence on earth. Where did this number come from? Well, if you wanted to break it down, you’d look at the number of habitable planets, the chance that life evolved on each one, the chance that each life would develop into advanced civilisation without dying, the estimated time since they developed advanced civilization, the estimated speed of travel weighted by the distance to us, the chance they would all “hide” from us, the chance they would decide to spy on us, etc. One of these has a roughly concrete answer, but all the others are just further speculative questions, with an utterly miniscule amount of evidence to go on for how hypothetical unobserved aliens would act. I think the uncertainty for most of these questions would range over many, many orders of magnitude, and that uncertainty will carry on into your final “prior”.
Assigning a single number to such a prior, as if it means anything, seems utterly absurd. It seems like it would be more reasonable, at the end of the analysis, to end up with something like a confidence interval. Ie: “I have a 95% interval that the probability of alien presence is between 1 in a quadrillion and 1 in 2”.
Thanks! :)
I don’t agree that it’s meaningless or absurd. A straightforward meaning of the number is “my subjective probability estimate if I had to put a number on it” — and I’d agree that one shouldn’t take it for more than that.
I also don’t think it’s useless, since numbers like these can at least help give a very rough quantitative representation of beliefs (as imperfectly estimated from the inside), which can in turn allow subjective ballpark updates based on explicit calculations. I agree that such simple estimates and calculations should not necessarily be given much weight, let alone dictate our thinking, but I still think they can provide some useful information and provoke further thought. I think they can add to purely qualitative reasoning, even if there are more refined quantitative approaches that are better still.
I guess my point of view is that for certain questions, we should stop forcing people to reduce their beliefs to a single number.
Say you told me to guess the number of advanced civilisations in our galaxy (other than humans), and, after meticulous research, I answered “1 million”. Does this singular number actually represent my belief? Would I be kicking myself and feeling like an idiot if the actual answer turned out to be 100?
Of course not. It’s a hugely uncertain, unboundedly speculative question. My actual beliefs are a spread of probabilities over a huge range of magnitudes, possibly quite unevenly spread (there would be a large bump at “0”). “1 million” would just be a snapshot of the median, and leave all that other information out.
The reason this matters is that EA frequently decides to make decisions, including funding decisions, based on these ridiculously uncertain estimates. You yourself are advocating for this in your article.
By reducing everything to that one number, we start influencing the next persons estimates, who influences the next person, and so on. Soon we end up with surveys of “alien experts” on the existential risk from aliens, asking them to estimate (P|aliens) as one number, which they inevitably anchor to the last estimate they saw, compounding everything until eventually you get treated like an absurdity for having a low estimate of Alien x-risk. All based on wildly, ridiculously uncertain initial guesses that someone made up once.
In summary, people should either start stating their uncertainty explicitly, or they should start saying “I don’t know”. This “1 number” status quo is just making things worse.
I think that misrepresents what I write and “advocate” in the essay. Among various other qualifications, I write the following (emphases added):
My claims about how I think these would be “weak to modest considerations in our assessments of how to act” are not predicated on the exact manner in which I represent my beliefs: I’d say the same regardless of whether I’m speaking in purely qualitative terms or in terms of ranges of probabilities.
FWIW, I do state uncertainty multiple times, except in qualitative rather than quantitative terms. A few examples:
To be clear, I think you included all the necessary disclaimers, your article was well written, well argued, and the use of probability was well within the standard for how probability is used in EA.
My issue is that I think the way probability is presented in EA is bad, misleading, and likely to lead to errors. I think this is the exact type of problem (speculative, unbounded estimates) where the EA method fails.
My specific issue here is how uncertainty is taken out of the equation and placed into preambles, and how a highly complex belief is reduced to a single number. This is typical on this forum and in EA (see P|doom). When bayes is used for science, on the other hand, the prior will be a distribution. (See the pdf of the first result here).
My concern is that EA is making decisions based on these point estimates, rather than on peoples true distributions, which is likely to lead people astray.
I’m curious: When you say that your prior for alien presence is 1%, what is your distribution? Is 1% your median estimate? How shocked would you be if the “true value” was 0.001%?
If probabilities of probabilities is confusing, do the same thing for “how many civilisations are there in the galaxy”.
It was in large part based on the considerations reviewed in the section “I. An extremely low prior in near aliens”. The following sub-section provides a summary with some attempted sanity checks and qualifications (in addition to the general qualifications made at the outset):