I hold that it is only when we can prove everything we assert that we understand perfectly the thing under consideration.

Take what you need, do what you should, you will get what you want.

Everything that is possible demands to exist.

Every present state of a simple substance is the natural consequence of its preceding state, in such a way that its present is big with its future.

Every mind has a horizon in respect to its present intellectual capacity but not in respect to its future intellectual capacity.

To love is to be delighted by the happiness of someone, or to experience pleasure upon the happiness of another. I define this as true love.

The greatness of a life can only be estimated by the multitude of its actions. We should not count the years, it is our actions which constitute our life.

Music is a hidden arithmetic exercise of the soul, which does not know that it is counting.

Imaginary numbers are a fine and wonderful refuge of the divine spirit almost an amphibian between being and non-being.

We may say, that not only the soul (the mirror of an indestructible universe) is indestructible, but also the animal itself is, although its mechanism is frequently destroyed in parts.

The present is saturated with the past and pregnant with the future.

Soar to heights where you may view the world from a new perspective.

There was no way to have a civilized conversation with that guy. It's like he was raised by giraffes or something.

We have witnessed the terrible increases in the incidence of alcoholism, the advent of drug dependency, the protests, marches, strikes and human alienation.

Art has always had as its test in the long term the ability to speak to our innermost selves.

War what is it good for? It's good for business.

Science cuts two ways, of course; its products can be used for both good and evil. But there's no turning back from science. The early warnings about technological dangers also come from science.

I don't go for very handsome men. Like they say in England, toy boys break too easily.

The best leaders collect information widely, listen to everybody, and then decide by themselves.

Facts do not give advice.

I burn with no causes.