Life is made up, not of great sacrifices or duties...

The most important of my discoveries have been suggested to me by my failures.

In the present state of our knowledge, it would be useless to attempt to speculate on the remote cause of the electrical energy... its relation to chemical affinity is, however, sufficiently evident. May it not be identical with it, and an essential property of matter?

How incessant and great are the ills with which a prolonged old age is replete.

The great secret that all old people share is that you really haven't changed in seventy or eighty years. Your body changes, but you don't change at all. And that, of course, causes great confusion.

Every great architect is - necessarily - a great poet. He must be a great original interpreter of his time, his day, his age.

Once I planned to write a book of poems entirely about the things in my pocket. But I found it would be too long and the age of the great epics is past.

Anyone who stops learning is old, whether at twenty or eighty. Anyone who keeps learning stays young. The greatest thing in life is to keep your mind young.

There is a fountain of youth: it is your mind, your talents, the creativity you bring to your life and the lives of people you love. When you learn to tap this source, you will truly have defeated age.

Life would be infinitely happier if we could only be born at the age of eighty and gradually approach eighteen.

Probably the happiest period in life most frequently is in middle age, when the eager passions of youth are cooled, and the infirmities of age not yet begun as we see that the shadows, which are at morning and evening so large, almost entirely disappear at midday.