The poor old earth which has mothered us and nursed us we treat with scant respect. Our awe and veneration we reserve for the worlds we know not of. Our senses sell us out. The mud on our shoes disenchants us.

Almost all of the governments have agreed that they will not acquire nuclear weapons and that they will allow the International Atomic Energy Agency to monitor their commercial and research nuclear power operations to ensure that nuclear materials - highly enriched uranium and plutonium - are not diverted to use in weapons.

To find the universal elements enough; to find the air and the water exhilarating; to be refreshed by a morning walk or an evening saunter... to be thrilled by the stars at night; to be elated over a bird's nest or a wildflower in spring - these are some of the rewards of the simple life.

Science has done more for the development of western civilization in one hundred years than Christianity did in eighteen hundred years.

Few persons realize how much of their happiness, such as it is, is dependent upon their work.

Natural history is a matter of observation; it is a harvest which you gather when and where you find it growing. Birds and squirrels and flowers are not always in season, but philosophy we have always with us. It is a crop which we can grow and reap at all times and in all places and it has its own value and brings its own satisfaction.

One can only learn his powers of action by action, and his powers of thought by thinking