I understand. But...
Let's cast this in terms of a good 100 word story. I recently wrote a 99 word flash fiction story myself. It's difficult to tell a whole story in a mere 99 word limit.
We can't begin to answer, as you well pointed out, how many possible ways life could have formed - therefore we cannot predict probabilities. Okay, you've made that point. It's a useful thought. Since we can't even have a discussion about something with so little basis of what is true about it, let's go to this 100 word story analogy.
Let's say the average word length in English is 6 letters and there are 27 letters including "space". The simplest approximation to the amount of information in a 100 word story is 600 letters. That is 27^600 possibilities or in base 10 it is 10^859 possibilities.
What is the chance of finding my 100 word story in this haystack? If we had each atom in the universe reading these 100 word "stories", 10^78 stories would be read per year and 10^88 stories would be read in the life of the universe. The ratio of 10^88 / 10^859 is tantamount to zero. Or stated differently, it would take 10^771 times the life of the universe to read all 100 word stories if every atom in the universe read a different story each and every second!
Ah, you say. But how many different stories can be written in English? Huge amounts of 100 word stories can be written in English! How do you calculate that? Let's say there are 10^5 English words. Now all the combinations of English 100 word stories is only 10^5^100, as a limit. Just because it is a concatenation of English words makes it a "story" not. But let's use this number 10^5^100 = 10^500 different stories. Hell, that's a lot of stories!
But while 10^500 stories is HUGE, it is a tiny fraction of all possible 600 letter combinations. 10^500 / 10^859 is tantamount to ZERO! That is, 10^-359 is such a vanishingly small value it IS zero for all practical purposes in our physical universe.
Now, I know I only made an argument for 100 word stories, but it is a reasonable analogy relating possible life-forms to possible English stories.
At least I think I brought something of substance to compare with. You are correct we cannot venture to guess how many different forms of life there could be. How many different periodic charts are possible if you jack around with physical laws? How many other worlds are possible that would support life - much less intelligent life. Who knows?
But it may be surprising to you, until you calculate it as I have done, that the amount of 100 word stories in English that could possibly have a flying chance of being a story, out of all 100 word letter-combinations, is ZERO for all practical purposes. I am prejudiced to be bent toward thinking that it is reasonable to also expect that the amount of possible "living worlds" is tantamount to ZERO in ratio to all possible things.
That is all the point I can make. The rest is just arguing about each other's biases and prejudices. ...this is more philosophy than science.
No, you don't understand.
You continue to adopt the "design mindset." Consequently, your analogy above is false, because you presume, a priori, that there is a subset of some total possibilities from which an organism will eventually arise to finally discuss the issue in this forum.
The above premise is simply false. We cannot work backward from our present state and estimate the odds of our being here, any more than we can estimate the odds of a ball falling into the slot of a roulette wheel containing no slots.
Prior to the universe existing, the odds of any particular future event occurring are equal, because given a set of limitless possibilities, all outcomes are equally likely.
To correct your analogy, you would have to take an infinite set of possible letters of infinite combination and then estimate the odds of an infinite number of possible stories of infinite length written in an infinite number of possible languages.
What are the odds of everything happening by chance, when selected from a set containing all possibilities?
Unity.
We are here, because it is inevitable, and it is not philosophy to say so. What IS philosophy is to say that "we" must be of some particular composition/nature, because we could have been anything, in any shape, size or composition.
If we had appeared in some other universe, made of gold instead of carbon, and the entire universe was constituted in a manner which permitted this, then that's what we would be.
Design is only meaningful in view of actual knowledge of the designer -- otherwise, given that infinite set of possibilities, even the designer's proverbial Boeing 747 could have occurred by pure accident in a universe which looked exactly like a junkyard.
Such a thought is only absurd, because we are here thinking such a thing from our perspective, But, in the universe where the 747 sits alone in the blackness of space, it's completely rational -- and in fact, it's the only possible outcome.
You have limited yourself to a mindset which prevents you from accepting that random chance can explain everything. Everything, that is, except for God, because God is the literal antithesis of randomness. If God exists, then randomness cannot, because God must know all in order to be God -- and randomness eschews all possible advance knowledge.
To bring this back to your English story analogy, could one million monkeys with typewriters bang out the complete works of Shakespeare, given sufficient time?
The answer is unequivocally, Yes. In our universe, this incredible accident actually occurred -- accomplished not by one million monkeys, but by only ONE!
His name, of course, was William Shakespeare.
N.B. And, he did it with a quill pen!