“Nothing is made from nothing.”

It is not enough to have a good mind; the main thing is to use it well.

I took especially great pleasure in mathematics because of the certainty and the evidence of its arguments.

Mind and soul of the man is entirely different from the body.

So far, I have been a spectator in this theatre which is the world, but I am now about to mount the stage, and I come forward masked.

With me, everything turns into mathematics.

In order to seek truth, it is necessary once in the course of our life to doubt, as far as possible, of all things

Except our own thoughts, there is nothing absolutely in our power.

I am accustomed to sleep and in my dreams to imagine the same things that lunatics imagine when awake.

In order to improve the mind, we ought less to learn than to contemplate.

I think; therefore I am.

To live without philosophizing is in truth the same as keeping the eyes closed without attempting to open them.

If you would be a real seeker after truth, it is necessary that at least once in your life you doubt, as far as possible, all things.

Bad books engender bad habits, but bad habits engender good books.

Whenever anyone has offended me, I try to raise my soul so high that the offense cannot reach it.

To think? That’s it. It is thought. This alone cannot be detached from me. I am, I exist; that is certain.

Divide each difficulty into as many parts as is feasible and necessary to resolve it.

The prince of darkness is a gentleman.

It’s not about how long we’ve been together but how deep our love is.

If there were no God, there would be no atheists.

You can’t control the length of your life. You can control the depth

God is like the sun; you cannot look at it, but without it you cannot look at anything else.

I know deep hurt. But I also know deep hope. Sometimes God’s power is shown as much in preventing things as it is in making them happen. We may never know why. But we can always know and trust the Who.

The world “out there” won’t change until the world “in here” does.

The disciples obey because that’s what people do when someone rises from the dead and gives instructions.