If you don't want to slip up tomorrow, speak the truth today.

Most of what matters in our lives takes place in our absence.

Knowing yourself is the beginning of all wisdom.

If you have no problems, then you have no clue to what is going.

Be frank and explicit. That is the right line to take when you wish to conceal your own mind and to confuse the minds of others.

Intellectuals solve problems, geniuses prevent them.

Do not deny the classical approach, simply as a reaction, or you will have created another pattern and trapped yourself there.

In anger we should refrain both from speech and action.

If you do what you've always done, you'll get what you've always gotten.

There are no eternal facts, as there are no absolute truths.

The secret of life, though, is to fall seven times and to get up eight times.

If we do not lay out ourselves in the service of mankind whom should we serve?

An understanding of the natural world is a source of not only great curiosity, but great fulfilment.

There are no limitations to the mind except those we acknowledge.

One just needs a little alertness to see and find out: Life is really a great cosmic laughter.

Desire is the very essence of man.

You always admire what you really don't understand.

To be one, to be united is a great thing. But to respect the right to be different is maybe even greater.

I think, therefore I am.

Strength does not come from physical capacity. It comes from an indomitable will.

Only idiots refuse to change their minds.