It suddenly struck me that that tiny pea, pretty and blue, was the Earth. I put up my thumb and shut one eye, and my thumb blotted out the planet Earth. I didn’t feel like a giant. I felt very, very small.
The single thing which makes any man happiest is the realization that he has worked up to the limits of his ability, his capacity. It’s all the better, of course, if this work has made a contribution to knowledge, or toward moving the human race a little farther forward.
