Supplemental chat with ChatGPT: https://chatgpt.com/share/68b1a923-4ebc-8003-9175-d10d258bc219
Suppose we get a single lightening flash (L) on my wedding(W). P(L|W). Now we try to estimate the probability. We get data on all lightening strikes and work out the probability it happens on a particular day. But there are 2 issues here.
(1) what does W "on my wedding mean" do we get data for the area, the country, the world and do we limit just to that day, month or perhaps it was a year with unusual weather? We have to make fuzzy choices about exactly what we are asking with W. But at least it is all about lightening L.
(2) But much more significant actually we are not really asking about lightening at all. We are asking "bad omens" B. We are asking P(B|W) what is the probability that some bad coincidence happened on my wedding. More broadly P(C|W) what is probability that any coincidence (C) happens on my wedding, and then dividing that into good/bad ones. And that is completely arbitrary and also quite probable. So even asking the question P(C|W) is fully dependent upon the asker. We could ask for a person P what is the probability they will notice a coincidence and get to trying to evaluate its probability... which could itself be viewed as a coincidence and in there is a proof against that kind of activity.
So while it looks like a fair question it is in fact completely arbitrary and indeterminate.
So same for what is the probability of intelligent life P(L|U). To evaluate U what do we mean: the known universe, or the unknown universe(s) as well? And L do we mean "me" or "humans" or "apes" of bacteria, viruses, or unknown forms of life. SETI will fail on all these except humans post 1895 (Marconi radio broadcast). So in a nutshell it is pointless and indefinable speculation.
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I missed the Existential element to this. In a moment of particular vivid self-consciousness we may feel that the Anthropic Principle is saying that because me, right here, right now, exists then the whole universe must exist. This is a version of Descartes famous cogito. It is invoking the idea of a fixed central singularity and self-knowing self to the world. This is problematic as Buddhism reveals. But much in the blog gets to the same place via Godel's demonstration of a broad principle (called SRH here*).
* SRH recap: Were a self a fixed thing, then the rest of the world would be separate and discrete from the self. To fully know the self would mean to be able to distinguish it from other things, which would be to go beyond the boundary of the self. So to know the self would be to know aspects of the non-self, and that means that the entity of self contains representations of what is non self which contradicts the idea that it is a fixed thing with discrete boundary.
So I missed a whole aura to this debate which is the added effect of it happening to "me." When lightening strikes at someone else's wedding it's a talking point, when it happens to "me" it is existential and seems to challenge the very foundations of existence. This is illusion. There is no difference between it happening to me and anyone else. Buddhism absolutely clears this mess up (that is its great achievement). One way to see that is to compare what we think about our self with what is there if we analyse it. When we analyse it (which is Vipassana meditation practice) we list all the things we can identify and what we get is a random bag of stuff (there are some sights, sounds, smells, touches, feelings, emotions, pains, thoughts etc etc) but not an actual self. The "self" is just the name of the bag, it is not an actual phenomenon. And in fact if we get really subtle we notice that "self" is just some of the thoughts so it's in the bag. If the bag is alongside the things we thought "in" the bag then there is no bag! So all events are just events, they happen to no one (there is no bag to hold them - getting rid of the bag idea IS Freedom and Enlightenment). Roll that back into lightening at my wedding: we now see it as lightening at "a" wedding, that happens to be mine (but there is no solid reality, substance or unifying element or bag to this second bit; there are thousands of weddings a year we it is just one of those.) So removing the existential element from the Anthropic Principle leaves a much cleaner situation. For any intelligent being to exist, the world obviously must be here and must be favourable for intelligence. That "I" exist is just a belief built from a stream of phenomena that contribute to an intelligent behaviour. "I" is not a necessary or needed part of an intelligent universe, in fact a really intelligent universe would have no "I"
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Original version:
Neo's passport in the Matrix expires on 11/9/2001 yet the film was released in 1999. That day is of great importance to East Coast Americans as Washington and New York both experienced simultaneous Saudi Arabian terrorist attacks. This is a great example of coincidence. We can ask the obvious question how did the film use a date of such future significance? To be an accident seems so unlikely. And that is the same question we often ask about Life or the Universe.
The Anthropic Principle is a truly profound idea with endless application and gives as a clear insight into this kind of problem. In the AP view of things we note that we start with intelligent life! The job is only to work backwards and work out how. That means that whenever intelligent life happens, you end up with consciousnesses sitting on the beach wondering how it all happened.
This feels very like paranormal investigation or the Neo's Passport coincidence above. Unlike a proper free statistical study where you start without the phenomenon P and choose XYZ conditions to see if you can create the phenomenon, with intelligent life (or paranormal) you are starting WITH the event P! It is now conditional. You are asking given P what was the chance of P happening assuming some XYZ. We need find the XYZ but it is open ended and is actually almost impossible. Given the coincidence that Neo's passport is one of the most significant days in American history, what was the probability of a coincidence in the film/hollywood/america/world/history of the universe etc we chose the XYZ. I guess the Neo coincidence is a bigger deal for Americans because they think 9/11 was a big deal for the world, when actually 9/11 was a deal for just a part of the US (think most American hicks saw it happening to the rich guys over there). That XYZ is open ended.
So we can't actually use any arguments about the "likelihood" because you can't construct the boundary XYZ. My own view is that the universe is infinite. So in an infinite amount of time whenever intelligent life occurs you get some people sitting on a beach going WOW how did this happen? They have literally no idea how infinite the space of possibility is.
That Neo above is a really good example of Paranormal and "creation." The way to human brain works and Uncanny is always talking about this Pareidolia, we look to put meaning into random things. The fact that Neo's passport expires on 11/9/2001 must be the result of intelligent design people think. Fore knowledge, conspiracy etc. If we didn't know the passport expired on 9/11 and someone asked what is the probability then we can come up with a small number. But it is the other way around. Likewise the emergence of human life is a small number, but given that it has already happened we need to ask the reverse question. Yet Paranormal looks for design and intelligence out there. Obvious circular: if you need intelligence to create intelligence you have a problem.