If the Universe Is Teeming with Aliens ... WHERE IS EVERYBODY?: Seventy-Five Solutions to the Fermi Paradox and the Problem of Extraterrestrial Life

by Stephen Webb

He argues that, in a steady-state era, knowledge will be the most valuable resource. Advanced ETCs would have a reason to leave a life-bearing planet well alone, if only because the planet will provide a non-renewable source of information.

non-renewable source of information