Doomsday argument

Quote: "The step that converts N into an extinction time depends upon a finite human lifespan. If immortality becomes common, and the birth rate drops to zero, then the human race could continue forever even if the total number of humans N is finite."

This is a fatal flaw in the argument, and it only reveals the isolation of philosophers from the realities of everyday life.

If we achieved a basis for biological immortality, that would only mean we would all ultimately fall prey to causes of death besides age and disease, like accidents.

Let's say there's a sum of probabilities that could cause death apart from biological ones, like car and other accidents that annually claims (example) 1% of modern people. According to the Binomial Theorem, such an annual risk probability would claim 55% of people after 80 years of life.

Given that, then assuming removal of any biological limit to life span, that nonbiological factor would produce a death rate of 86% after 200 years and 98% after 400 years.

So even if we achieve immortality, we don't achieve immortality.

I think philosophers should all be forced to take a course in reality.