What is the foundation of civilization?
Others might have many answers, but Lu Yuanming knew the essence of it: energy!
It's not just about civilization; the foundation of all life is energy!
In any environment, at any stage of civilization, under any form of life, as long as it's a living being, energy is the foundation of everything.
Before the birth of intelligence, every form of life competed for the right and efficiency of gaining energy. Taking Earth as an example, from single-celled organisms to fish, dinosaurs, mammals, and eventually to humans, all followed this core principle: energy acquisition.
From the emergence of civilizations, to their progress, to stepping off Earth, the advancement was all about the efficiency, amount, and security of energy acquisition, and so on.