If you pick up a starving dog and make him prosperous, he will not bite you; that is the principal difference between a dog and a man.
It is a true saying that 'One falsehood leads easily to another'.
It is a great thing to know our vices.
Where the senses fail us, reason must step in.
Doubt is the father of invention.
You cannot teach a man anything; you can only help him discover it in himself.
The sun, with all those planets revolving around it and dependent on it, can still ripen a bunch of grapes as if it had nothing else in the Universe to do.
I have never met a man so ignorant that I couldn't learn something from him.
All truths are easy to understand once they are discovered; the point is to discover them.
I do not feel obliged to believe that the same God who has endowed us with sense, reason, and intellect has intended us to forgo their use.