To stay young requires unceasing cultivation of the ability to unlearn old falsehoods.
Robert A. HeinleinSeems to be a deep instinct in human beings for making everything compulsory that isn't forbidden.
Robert A. HeinleinAnimals can be driven crazy by placing too many in too small a pen. Homo sapiens is the only animal that voluntarily does this to himself.
Robert A. HeinleinLiberty is never unalienable, it must be redeemed regularly with the blood of patriots or it always vanishes.
Robert A. HeinleinThe Stone trembled and threw herself outward bound, toward Saturn. In her train followed hundreds and thousands and hundreds of thousands of thousands of restless, rolling Stones . . . to Saturn . . . to Uranus, to Pluto . . . rolling on out to the stars . . . outward bound to the ends of the Universe.
Robert A. Heinlein