The Door into Summer

by Robert A. Heinlein

I have spent too much of my life opening doors for cats—I once calculated that, since the dawn of civilization, nine hundred and seventy-eight man-centuries have been used up that way. I could show you figures.

Connecticut winters are good only for Christmas cards;

Los Angeles was safe from invasion; the invaders wouldn’t find a place to park—

What was there small enough for one engineer and not requiring six million man-hours before the first model was on the market? Bicycle-shop engineering with peanuts for capital, the way Ford and the Wright brothers had started—people said those days were gone forever; I didn’t believe it.