You’ll miss the best things if you keep your eyes shut.

That which can be asserted without evidence, can be dismissed without evidence.

I do not argue with obstinate men. I act in spite of them.

A scientific man ought to have no wishes, no affections, - a mere heart of stone.

Only those with no memory insist on their originality.

He who possesses most must be most afraid of loss.

The true test of a man's character is what he does when no one is watching.

Your personal nature seeks its paradise.

There are two things children should get from their parents: roots and wings.

His modesty amounts to deformity.

Children's talent to endure stems from their ignorance of alternatives.

There is no limit to the amount of good you can do if you don't care who gets the credit.

There is not such a cradle of democracy upon the earth as the Free Public Library, this republic of letters, where neither rank, office, nor wealth receives the slightest consideration.

No one can make you feel inferior without your consent.

Radical simply means 'grasping things at the root'.

I must uphold my ideals, for perhaps the time will come when I shall be able to carry them out.

A photograph can be an instant of life captured for eternity that will never cease looking back at you.

One of the advantages of being disorderly is that one is constantly making exciting discoveries.

There is no such thing as a Christian child: only a child of Christian parents.

When the student is ready, the teacher will appear.

Enthusiasm... the sustaining power of all great action.