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The question for discussion is exactly how much luck was involved in the development, on Earth, of life from non-living substances, and, as a corollary, what chance there is of finding life on any other Earth-like planet.
To go about this systematically, let us first decide what (from a chemical standpoint) non-life is, and what (from a chemical standpoint), life is, and then, perhaps, we can see how non-life may turn into life.
But let's see, is there life on Mars?
Despite all the odds against it, despite the poorness of the planet, the answer seems to be: possibly yes. At least, the green areas on Mars seem to signify some kind of vegetation. The vegetation might be very primitive and undiversified, nothing like the teeming life of Earth, but it would be life.
And if Mars can do it, then it is my belief that any Earth-like planet can do it.
As Asimov so directly states in his opening paragraphs, this essay discusses how much luck is involved in the creation of life. He argues that "blind chance" has nothing to do with the liklihood of how life was formed on Earth, and may be formed on other planets.
He makes the point that random factors would make it impossible for life to develop, except that the development of life isn't random...certain atoms will combine with other atoms in a handul of ways, but no more than that. Thus, if you stick your hand in a vatful of marbles, chances are you will pick out one of each kind, but if you stick your hand in a vatful of atoms, you'll draw out several of the same kind or like groupings, because certain atoms will combine, but they will only combine in a limited number of ways. (For example, 2 hydrogen and 1 oxygen atoms unite to form water.) (Okay, Asimov explained it better.)
To paraphrase a famous saying: Nucleoprotein is the whole of life, all else is commentary.
In the 1976 edition, Asimov provides a note at the end of this essay:
Since July 1956, when this essay was first written [For Amazing], chemists have continued the kind of work Miller initiated and have shown in great detail the manner in which even some quite complicated chemicals can be formed without the intervention of cellular life, although they have come nowhere near life itself even yet.
Tiny traces of organic materials of the kind pointing toward life have been found in meteorites: and these show signs of having been formed without the intervention of living cells. In the 1970s, astronomers detected simple organic molecules in the dust-clouds of outer space. Apparently, the kind of molecules that seem to point toward life form whenever they are given the slightest chance to do so.)