One way of saving on energy use would be to do away with unnecessary transportation. For instance, people commute between work and home, or travel lo… - Isaac Asimov

Ahora era precisamente aquel mundo frío, gris y miserable que le había parecido en un principio, pero su gente estaba llena de calor y vida. Era gente real, sólida. Solaria, Aurora, los otros mundos espaciales que había visitado o contemplado en hipervisión, parecían llenos de gente insustancial, «gaseosa». Esa era la palabra. «Gaseosos.»

It is an odd fact that anyone who wishes to start a war must always make it appear that he is fighting in a just cause even if the real motive is naked aggression. Fortunately for the would-be aggressor, a "just cause" is very easy to find.

What phrase was that, sir?" "You said something about interviewing people face to — — " He shook his head, his tongue dabbing quickly at his lips. "I would rather not say it. I think you know what I mean. The phrase conjured up the most striking picture of the two of us breathing — breathing one another's breath." The Solarian shuddered. "Don't you find that repulsive?" "I don't know that I've ever thought of it so." "It seems so filthy a habit. And as you said it and the picture rose in my mind, I realized that after all we were in the same room and even though I was not facing you, puffs of air that had been in your lungs must be reaching me and entering mine. With my sensitive frame of mind — — " Baley said, "Molecules all over Solaria's atmosphere have been in thousands of lungs. Jehoshaphat! They've been in the lungs of animals and the gills of fish.