Harold Squared

All over North America there are remnants of the "Mound Builders" civilization, but I understand what you mean, trees represent fuel, and Russian winters are notoriously harsh. Much of New England was stripped of trees before coal came into widespread use.

Indeed, concealment of military formations. In medieval times trees were cut and the sharpened branches laid towards the enemy, they are called "abatis". In the days of the Raj, a great hedge was maintained to keep the inland population from getting salt from the sea. This hedge has largely disappeared but was very effective in its day.

Without imagination there is no progress, indeed all of mathematics is a work of imagination, in the sense of abstract concepts, ideas outside our purely sensory experience. But yes, imagination without discipline(another imagined concept) is worthless. Is it surprising or not that we can express such abstractions more precisely to each other than sense perceptions? I struggle to describe sunsets to the blind or symphonies to the deaf but we assume that even intelligent beings not native to this planet can grasp mathematics and so we start from there. All the positive thinking in the world won't get you out of a concentration camp. I am pretty sure there are other limitations too. On the other hand, pessimism has defeated many who have yet to begin. This is a symptom of a truly robust imagination! Lol... The paradox has its function though. By definition, atoms are indivisible, how can they split? Yet they do split, both spontaneously and by our design. Nature cares nothing for our definitions, so we redefine our terms accordingly. And our body of knowledge profits thereby. What was once "impossible" yields vast power both for destruction and beneficial service.

You're so right. Wonderful thread, obviously a labor of love. I am a LFTR fan but I think the power output of fusion should enable very robust construction and the lighter weight of fuel would be advantageous. It would be nice to compare these bad boys in the flesh, wouldn't it? Are you familiar with the Project Rho website?

Nice! One minor quibble, you do not seem to have included the very likely development of fusion power which would facilitate the venture.

Fans of this topic and sex research generally are referred to Mary Roach's "Bonk". An amusing overview of the field suitable for almost all readers.