all these human progress discussions imply, or bounded by, one hypothesis - there will exist only one species of humans. Is divergence of the species into 2 or more is such an unprobable event?
No, no they really aren't. There is essentially no dependence on "humans" in that discussion. "Intelligent species" can be substituted with no loss or even substantial change in meaning. The point is that an intelligent, active technological civilization is not intrinsically unsustainable. Bringing up your point would just open a distracting side discussion not terribly relevant to the author's point.
>an intelligent, active technological civilization is not intrinsically unsustainable.
that would be bad. No need to evolve in any cardinal way. Only needed changes would be minor adjustments to fit humans most comfortably into the tecnological civilization cradle. Just like dinosaurs who evolved to fit most comfortably into their Earth dominating niche ... until the meteor stroke, super vulcanos erupted , etc...
Anyway, i don't agree that technological civilization is not intrinsically unsustainable. The civilization has already established its exponential nature. Good thing about exponentially increasing speed is quickly hitting whatever natural limits are there, and that induces need for change. Yes, in many cases we naturally prognose (McCarty incl.) the response to be a new improved technology. Yet, artificially limiting human species response to a need for change only to technological type of responses seems ... artificial.
The problem with running up against the limits is that it isn't always pretty. I've heard it said that "all exponential functions are really S-curves" which in this situation would correspond to a civilisation gracefully decreasing its growth as it approached the limits.
However, other curves are possible too. Overshoot and collapse can also occur.
The S-curve scenario can only happen under the following circumstances.
a) the limits are recognised by us
b) they are responded to immediately with no delay.
Another scenario, called "overshoot and oscillation" occurs when:
a) there is a delay in the response
b) AND the the limits that we have exceeded recover quickly. i.e. the limits are no erodable.
"Overshoot and collapse" occurs when we erode some resource that does not recover quickly. Unfortunately, I can think of many resources that are very erodable. The most obvious being fossil fuels which take millions of years to replace themselves. Top-soil and biodiversity are also examples of highly erodable resources.
"that would be bad. No need to evolve in any cardinal way... until the meteor stroke, super vulcanos erupted , etc..."
Again, you bring more assertions out of thin air, this time actively contradicting the source. McCarthy explicitly mentions space colonization, though he doesn't make it a central part of his argument. Who anywhere said the only response to change would be technological? You're criticizing McCarthy for ideas that you're the one bringing up in the first place. That's not fair.
