Pirkei Avot §avot_05_07: [There are] seven things [characteristic] in a clod, and seven in a wise man:...

[There are] seven things [characteristic] in a clod, and seven in a wise man: A wise man does not speak before one who is greater than he in wisdom, And does not break into his fellow’s speech; And is not hasty to answer; He asks what is relevant, and he answers to the point; And he speaks of the first [point] first, and of the last [point] last; And concerning that which he has not heard, he says: I have not heard; And he acknowledges the truth. And the reverse of these [are characteristic] in a clod.