There's no system foolproof enough to defeat a sufficiently great fool.

Society's emissions of carbon dioxide may or may not turn out to have something significant to do with global warming-the jury is still out.

When you're certain you cannot be fooled, you become easy to fool.

A fact is a simple statement that everyone believes. It is innocent, unless found guilty. A hypothesis is a novel suggestion that no one wants to believe. It is guilty, until found effective.

When you come to the end of all the light you know, and it's time to step into the darkness of the unknown, faith is knowing that one of two things shall happen: either you will be given something solid to stand on or you will be taught to fly.

The best weapon of a dictatorship is secrecy; the best weapon of a democracy is openness.

Today, nothing is unusual about a scientific discovery's being followed soon after by a technical application: The discovery of electrons led to electronics; fission led to nuclear energy. But before the 1880's, science played almost no role in the advances of technology. For example, James Watt developed the first efficient steam engine long before science established the equivalence between mechanical heat and energy.