Any intelligent fool can make things bigger and more complex... It takes a touch of genius --- and a lot of courage to move in the opposite direction.Another one of his I like a lot is:
I want to know God's thoughts...the rest are details.This may help explain why, in his personal life, he was so detached from his family, and, in general, so skeptical of anyone in authority.
There are many more good ones at the link above. If you like them even half as much as I do, then you would also enjoy Ideas and Opinions. It is a collection of many of his essays, speeches and letters. At least one piece was for the Sunday New York Times. Some are on science, but more, I believe, are on education, religion and politics. It is mostly very accessible stuff, believe it or not. Two-thirds of the book can be understood by anyone who went to high school.
Some of his thinking on politics will seem too idealistic to almost everyone, and does to me. I still like seeing how he thinks things through. This is literally the book I would take with me to a desert island, if I could take only one.