Whenever a new finding is reported to the world people say - It is probably not true. Later on, when the reliability of a new finding has been fully confirmed, people say - OK, it may be true but it has no real significance. At last, when even the significance of the finding is obvious to everybody, people say - Well, it might have some significance, but the idea is not new.

... whoever believes anything esteems that it is a work of charity to persuade another of it.

The world always looks straights ahead; as for me, I turn my gaze inward, I fix it there and keep it busy. Everyone looks in front of him: as for me, I look inside me: I have no business but with myself; I continually observe myself, I take stock of myself, I taste myself. Others...they always go forward; as for me, I roll about in myself.

Oh senseless man, who cannot possibly make a worm or a flea and yet will create Gods by the dozen!

Wonder is the foundation of all philosophy; research, the progress; ignorance, the end. There is, by heavens, a strong and generous kind of ignorance that yields nothing, for honour and courage, to knowledge: an ignorance to conceive which needs no less knowledge than to conceive knowledge.

The lack of wealth is easily repaired but the poverty of the soul is irreplaceable.

It is a sign of contraction of the mind when it is content, or of weariness. A spirited mind never stops within itself; it is always aspiring and going beyond its strength.