The man who views the world at fifty the same as he did at twenty has wasted thirty years of his life.

– Muhammad Ali

Seven characteristics distinguished the wise: he does not speak in the presence of one wiser than himself, does not interrupt, is not hasty to answer, asks and answer the point, talks about first things first and about last things last, admits when does not know, and acknowledge the truth.

– Talmud

Wisdom is knowing what to do next; skill is knowing how to do it, and virtue is doing it.

– David Starr Jordan