The rocks are not so close akin to us as the soil; they are one more remove from us; but they lie back of all, and are the final source of all. ... Time, geologic time, looks out at us from the rocks as from no other objects in the landscape.

To learn something new, take the path that you took yesterday.

How much there is in books that one does not want to know, that it would be a mere weariness and burden to the spirit to know.

He who marvels at the beauty of the world in summer will find equal cause for wonder and admiration in winter.

I still find each day too short.

The only countries that are outside of [ Nuclear Non-Proliferation Treaty] are Israel, Pakistan, India, and North Korea withdrew in the last few years.

The rocks have a history; gray and weatherworn, they are veterans of many battles; they have most of them marched in the ranks of vast stone brigades during the ice age; they have been torn from the hills, recruited from the mountaintops, and marshaled on the plains and in the valleys; and now the elemental war is over, there they lie waging a gentle but incessant warfare with time and slowly, oh, so slowly, yielding to its attacks!