On  1-Aug-2003, david@djwhome.demon.co.uk (David Woolley) wrote:

One of the problems we already face is that we are getting to the point
where we could never recover from a fall because the natural resources
needed to manufacture technology have been degraded to the point where
high levels of technology are needed to extract them.

WIth enough time, alternative technologies using different resources can be
developed.

It is this last point, rather than population explosion, that means that
a truly successful technological species must emigrate to other stars.
At the moment, I think it much more likely that we will leave it too late,
to when we no longer have the time or resources to do it.

This last statement is an oxymoron.   When SHOULD we leave?

I repeat that the degradation of natural resources makes it more and more
difficult for each generation to create technology.

This degradation has been going on for a long, long time.    Has this
increase in difficulty been going on a long, long time as well?