|
|
|
|
|
|
by _yb2s
1066 days ago
|
|
|
Please try to keep the discourse civil. You have not understood my argument. What you are dismissing as obviously wrong is a well known mathematical fact [1]. Imagine the “space” of all currently unobserved phenomena that require a series of independent hurdles to be overcome a la the drake equation: observable aliens, etc. This space is infinitely big and the probability of each of the hypothetical phenomena is astronomically low as to not even be worth considering. The ones that are worth considering have some evidence that either they have occurred, or that we think we understand the process by which they come about, and all of the series of independent hurdles are likely to be nonzero. Imagine this simple test: take a random sample of 7+ numbers on [0,1] and multiply them together as the Drake equation does. Repeat this thousands of times to plot a smooth density plot, and you will get a stretched exponential distribution, with the majority of the probability density near zero. This type of causal process with a cascade of independent filters multiplied together that leads to a stretched exponential is common in a lot of domains[1], and almost always makes positive outcomes very rare. For example, the probability that some random new organic molecule will bind to a specific protein target to be an effective drug is similar in this way, and is close to zero. For a molecule to work as a drug it has to pass a lot of hurdles just as a civilization does in the Drake model: be bioavailable, bind to the right target in the right way, not bind to harmful targets, be metabolized at a reasonable rate, etc. [1] https://link.springer.com/article/10.1007/s100510050276 |
|
|
You’re implying that there are many things that could go wrong, and that if we took a random sample of “things” that we would probably find some joint distribution that is small. This is true in the sense that an incalculably small proportion of conceivable things happen.
But this particular thing is not a random sample of things. You don’t get to appeal to the unknown distribution of distributions. Your claim that it “ almost always makes positive outcomes very rare” is completely irrelevant to non randomly chosen and defined processes.
You can’t insert steps into a Bayesian inference until your priors match a desired outcome. It’s as fallacious as inserting an infinite number of steps that are highly likely but technically possible to not be the case as a way to reduce any given prior from basically guaranteed to basically never expected to happen.
Your argument reduces to “I don’t know what decides the probability of alien life but I think the chance is small” which is a fine opinion, but your mathemagics have not strengthened your argument.
Suppose we play a game called “the four game” in which case you have to guess if I’m thinking of the number 4. By your reasoning you would probably guess 0% because you don’t know the rules of generation and there are infinite conceivable ways I could draw numbers from and 1 out of infinite draws will be exactly 4. But when I play the four game I always think of 4. The imagined sampling of unknown distributions is irrelevant because the game itself is not random.
Now, look, the Drake equation tries to do it all, and that’s probably bad. Let’s re imagine it as a function that simply identifies a probability of alien life, by now, on a randomly chosen planet, multiplied by the total number of planets out there right now (let’s ignore the detectable part). Is the probability part really small? Well yeah almost certainly. No math required. Is it small enough that we can provide any confidence on the order of magnitude of the expected value? Nope. The only interesting question, imo, is whether that expected value is greater than or less than one.
The drug example you have provided is a case of exploring a new space. This is not comparable to life appearing on a planet. Because like a novel drug development, we have an example of life originating on a planet. It’s not a random sample either but it’s sufficient to observe that the process to make this happen exists and has happened. Unlike the drug development which largely a test of whether the pattern exists or not.