Those whose conscience demands that they defy authority in some ways that involve great consequences must be willing to accept some penalty.

In the long run our boasted control of nature is a delusion.

As machines get to be more and more like men, men will come to be more like machines.

There is no conceivable human action which custom has not at one time justified and at another condemned.

In our hearts those of us who know anything worth knowing know that in March a new year begins, and if we plan any new leaves, it will be when the rest of Nature is planning them too.

We must not judge the society of the future by considering whether or not we should like to live in it; the question is whether those who have grown up in it will be happier than those who have grown up in our society or those of the past.

We need some contact with the things we sprang from. We need nature at least as a part of the context of our lives. Without cities we cannot be civilized. Without nature, without wilderness even, we are compelled to renounce an important part of our heritage.