War is only an invention, not a biological necessity.

Earth Day is the first holy day which transcends all national borders, yet preserves all geographical integrities, spans mountains and oceans and time belts, and yet brings people all over the world into one resonating accord, is devoted to the preservation of the harmony in nature and yet draws upon the triumphs of technology, the measurement of time, and instantaneous communication through space.

What the world needs is not romantic lovers who are sufficient unto themselves, but husbands and wives who live in communities, relate to other people, carry on useful work and willingly give time and attention to their children.

Children must be taught how to think, not what to think.

Our human situation no longer permits us to make armed dichotomies between those who are good and those who are evil, those who are right and those who are wrong. The first blow dealt to the enemy's children will sign the death warrant of our own.

the task of each family is also the task of all humanity. This is to cherish the living, remember those who have gone before, and prepare for those who are not yet born.

If one cannot state a matter clearly enough so that even an intelligent twelve-year-old can understand it, one should remain within the cloistered walls of the university and laboratory until one gets a better grasp of one's subject matter.