Tolerance always has limits - it cannot tolerate what is itself actively intolerant.

Everyone who remembers his own education remembers teachers, not methods and techniques. The teacher is the heart of the educational system.

To silence criticism is to silence freedom.

I was guilty of judging capitalism by its operations and socialism by its hopes and aspirations; capitalism by its works and socialism by its literature.

The easiest rationalization for the refusal to seek the truth is the denial that truth exists.

Fear of death has been the greatest ally of tyranny past and present.

The difference between science and religion is that the former wishes to get rid of mysteries whereas the latter worships them.

Nonetheless, it still remains true that as a set of cognitive beliefs, religious doctrines constitute a speculative hypothesis of an extremely low order of probability.

In contrast to totalitarianism, democracy can face and live with the truth about itself.

Before impugning an opponent's motives, even when they legitimately may be impugned, answer his arguments.

Students rarely disappoint teachers who assure them in advance that they are doomed to failure.

Average leaders take you to the mountain.Superior leaders take you up the mountain.Excellent leaders take you to mountaintop.Transcendent leaders take you to the stars.

The only technology that helps to create a plethora of business and employment opportunity while promoting the green environment, is serving good for the society and, therefore, the sustainability.

The appetite for silence is seldom an acquired taste.

There is the plain fool who does the wrong thing at all times anywhere, but there is the Wall Street fool who thinks he must trade all the time.

The true value of communication is often not so much what you say to each other but the simple, powerful fact that you care enough to say something to each other so often.

Grey time-worn marbles Hold the pure Muses. In their cool gallery, By yellow Tiber, They still look fair.

For every scientific (or engineering) action, there is an equal and opposite social reaction.

When a government official says a problem has been "contained," pay no attention.

It's a tough job to tell a story when the audience already knows the ending, and the ending is bleak.

He hits from both sides of the plate. He's amphibious.