The point is that if they influence other people's children into being atheists too, then the atheist section of the population grows.
If your argument is that an entirely atheist population would eventually die out altogether (having no other children to convert) then I misunderstood, but still that an equilibrium will be reached.
I believe you are right that the equilibrium will be determined by the conversion and birth/death coefficients. But that equilibrium may still be at the point of zero atheists! The continued existence of every group still depends on (children + conversions_to - conversions_from) > 2.0 (per breeding pair).
Furthermore, it seems plausible that conversion to a group depends positively on the dominance that group (e.g., more opportunities to be converted as you interact with random others in daily life).
So all else being equal (or unknown), then my money's on the group with the highest birth rate.
Ah, so I did misinterpret your statement first time 'round?
I was thinking that "children" may be a function of total population. At least below some threshold people may have more kids than they would otherwise out of a sense of "duty", or the desire for continuation of the species (which seems to be inherent -- people sacrificing themselves to save "the world" usually do it to safe humanity).
We'll just go with me being unclear and possibly confused on that first round.
If, in reality, people are having children out of a sense of duty to save the world from extinction due to underpopulation then I'm wondering why I didn't get the memo.
Not that they are having them for that reason currently, but it's not implausible they would start were the total human population of earth to drop below, say, 100k.
