If I try to answer that question as written, I’d say that any time I see a probability estimate with on-the-order-of-hundreds of zeroes, when I know that event actually happened (at least) once in Earth’s past light cone, I’m going to assume there is an error in the model that generated the estimate, whether I know what it is or not.
I would agree for pretty much any other topic. This is an event required for people to be around to observe it. Imagine a universe in which abiogenesis events really were absurdly rare- unlikely to ever occur in a given observable universe sized area. Every observer in this universe would still look back and see an abiogenesis event occurring in their past! Having observed exactly one event is completely required and provides no evidence. This is essentially the weak anthropic principle.
The fact that we observe only exactly one event is thus bayesian evidence in the direction of rare abiogenesis. You bring up the point that the fact we observe only exactly one event in earth’s history isn’t that strong of evidence because e.g. events being concealed by significantly more advanced competitors. I certainly don’t disagree- that was just unfortunate overemphasis on my part.
So what I way trying to point to is that if a catalytic cycle of many (much smaller) RNA strands was sufficient for an abiogenesis event, that could lower the probability estimate enough to make such events more likely by enough that there could have been multiple even just on Earth without straining credulity, and the world today would likely look basically the same either way since the more-competitive biochemistry would have long since reach fixation (and/or the lineages could have merged in some analog of later endosymbiosis events).
I was thinking of systems more complex than the random coalescence of nucleotides when I wrote my post, but I didn’t know how to productively model that. Someone else had a similar argument and I responded that I slightly shifted away from rare-abiogenesis because I wasn’t thinking of complicated groups of cross-catalyzing RNA in particular, which are dumb enough to have no modern analogues but not so dumb as to not be competitive against single-strand solutions which require the random coalescence of another 100 base pairs, or whatever it is. It’s unclear to what degree this should affect my model, given a lack of understanding of how such systems work.
I would agree for pretty much any other topic. This is an event required for people to be around to observe it. Imagine a universe in which abiogenesis events really were absurdly rare- unlikely to ever occur in a given observable universe sized area. Every observer in this universe would still look back and see an abiogenesis event occurring in their past! Having observed exactly one event is completely required and provides no evidence. This is essentially the weak anthropic principle.
The fact that we observe only exactly one event is thus bayesian evidence in the direction of rare abiogenesis. You bring up the point that the fact we observe only exactly one event in earth’s history isn’t that strong of evidence because e.g. events being concealed by significantly more advanced competitors. I certainly don’t disagree- that was just unfortunate overemphasis on my part.
I was thinking of systems more complex than the random coalescence of nucleotides when I wrote my post, but I didn’t know how to productively model that. Someone else had a similar argument and I responded that I slightly shifted away from rare-abiogenesis because I wasn’t thinking of complicated groups of cross-catalyzing RNA in particular, which are dumb enough to have no modern analogues but not so dumb as to not be competitive against single-strand solutions which require the random coalescence of another 100 base pairs, or whatever it is. It’s unclear to what degree this should affect my model, given a lack of understanding of how such systems work.