True education is the ability to discern the difference between what you do know and what you don't.

The heart errs like the head; its errors are not any the less fatal, and we have more trouble getting free of them because of their sweetness.

The future is a convenient place for dreams.

We have drugs to make women speak, but none to keep them silent.

We find it hard to picture to ourselves the state of mind of a man of older days who firmly believed that the Earth was the centre of the Universe, and that all the heavenly bodies revolved around it. He could feel beneath his feet the writhings of the damned amid the flames; very likely he had seen with his own eyes and smelt with his own nostrils the sulphurous fumes of Hell escaping from some fissure in the rocks. Looking upwards, he beheld ... the incorruptible firmament, wherein the stars hung like so many lamps.

For a man’s life would become intolerable, if he knew what was going to happen to him. He would be made aware of future evils, and would suffer their agonies in advance, while he would get no joy of present blessings since he would know how they would end. Ignorance is the necessary condition of human happiness, and it has to be admitted that on the whole mankind observes that condition well. We are almost entirely ignorant of ourselves; absolutely of others. In ignorance, we find our bliss; in illusions, our happiness.

The first virtue of all really great men is that they are sincere. They eradicate hypocrisy from their hearts.