What goes up must come down.

There is nothing more frightful than ignorance in action.

Middle age has been defined as what happens when a person's broad mind and narrow waist change places.

Even when you think you have your life all mapped out, things happen that shape your destiny in ways you might never have imagined.

Nothing in life is to be feared, it is only to be understood. Now is the time to understand more, so that we may fear less.

Certain signs precede certain events.

As far as we can discern, the sole purpose of human existence is to kindle a light of meaning in the darkness of mere being.

Do not erase the designs the child makes in the soft wax of his inner life.

But I don't want comfort. I want God, I want poetry, I want real danger, I want freedom, I want goodness. I want sin.

Life belongs to the living, and he who lives must be prepared for changes

Take care of your body. It's the only place you have to live.

Until you value yourself, you won't value your time. Until you value your time, you will not do anything with it.

We were all at once terribly alone; and alone we must see it through.

Everything existing in the universe is the fruit of chance and necessity.

To do a great right do a little wrong.

Fortune cannot aid those who do nothing.

History repeats itself, first as tragedy, second as farce.

Have no fear of perfection - you'll never reach it.

I’m not afraid of death, but I’m in no hurry to die. I have so much I want to do first.

We live in a society exquisitely dependent on science and technology, in which hardly anyone knows anything about science and technology.

Science is the most reliable guide for civilization, for life, for success in the world. Searching a guide other than the science is meaning carelessness, ignorance and heresy.