We amuse ourselves painting our prison-walls with bright figures and brilliant landscapes.

Man believes himself always greater than he is, and is esteemed less than he is worth.

I could never have known so well how paltry men are, and how little they care for really high aims, if I had not tested them by my scientific researches. Thus I saw that most men only care for science so far as they get a living by it, and that they worship even error when it affords them a subsistence.

Rest not. Life is sweeping by; go and dare before you die. Something mighty and sublime, leave behind to conquer time.

It is easier to perceive error than to find truth, for the former lies on the surface and is easily seen, while the latter lies in the depth, where few are willing to search for it.

Our modern wars make many unhappy while they last and none happy when they are over.

And step by step, along the path of life, There's nothing true but Heaven.