“The wise man's rule is worth much more to him than the fool's revenue.”

Maxim 49
Sentences, The Moral Sayings of Publius Syrus, a Roman Slave

Plutarch's Life of Cato
Variant: Wise men profit more from fools than fools from wise men; for the wise men shun the mistakes of fools, but fools do not imitate the successes of the wise.

Life of Marcus Cato
Bartlett's Familiar Quotations, 10th ed. (1919)

Compare Poor Richard's Almanack (1749) : The wise Man draws more Advantage from his Enemies, than the Fool from his Friends.
Introductio ad prudentiam: Part II (1727), Gnomologia (1732)

Letter to Evert Augustus Duyckinck (3 March 1849); published in The Letters of Herman Melville (1960) edited by Merrell R. Davis and William H. Gilman, p. 78; a portion of this is sometimes modernized in two ways:
Context: I do not oscillate in Emerson's rainbow, but prefer rather to hang myself in mine own halter than swing in any other man's swing. Yet I think Emerson is more than a brilliant fellow. Be his stuff begged, borrowed, or stolen, or of his own domestic manufacture he is an uncommon man. Swear he is a humbug — then is he no common humbug. Lay it down that had not Sir Thomas Browne lived, Emerson would not have mystified — I will answer, that had not Old Zack's father begot him, old Zack would never have been the hero of Palo Alto. The truth is that we are all sons, grandsons, or nephews or great-nephews of those who go before us. No one is his own sire. — I was very agreeably disappointed in Mr Emerson. I had heard of him as full of transcendentalisms, myths & oracular gibberish; I had only glanced at a book of his once in Putnam's store — that was all I knew of him, till I heard him lecture. — To my surprise, I found him quite intelligible, tho' to say truth, they told me that that night he was unusually plain. — Now, there is a something about every man elevated above mediocrity, which is, for the most part, instinctuly perceptible. This I see in Mr Emerson. And, frankly, for the sake of the argument, let us call him a fool; — then had I rather be a fool than a wise man. —I love all men who dive. Any fish can swim near the surface, but it takes a great whale to go down stairs five miles or more; & if he don't attain the bottom, why, all the lead in Galena can't fashion the plumet that will. I'm not talking of Mr Emerson now — but of the whole corps of thought-divers, that have been diving & coming up again with bloodshot eyes since the world began.
I could readily see in Emerson, notwithstanding his merit, a gaping flaw. It was, the insinuation, that had he lived in those days when the world was made, he might have offered some valuable suggestions. These men are all cracked right across the brow. And never will the pullers-down be able to cope with the builders-up. And this pulling down is easy enough — a keg of powder blew up Block's Monument — but the man who applied the match, could not, alone, build such a pile to save his soul from the shark-maw of the Devil. But enough of this Plato who talks thro' his nose.

Of Boldness
Essays (1625)

Introductio ad prudentiam: Part II (1727)

1840s, Essays: First Series (1841), Compensation
Context: We feel defrauded of the retribution due to evil acts, because the criminal adheres to his vice and contumacy, and does not come to a crisis or judgment anywhere in visible nature. There is no stunning confutation of his nonsense before men and angels. Has he therefore outwitted the law? Inasmuch as he carries the malignity and the lie with him, he so far deceases from nature. In some manner there will be a demonstration of the wrong to the understanding also; but should we not see it, this deadly deduction makes square the eternal account.
Neither can it be said, on the other hand, that the gain of rectitude must be bought by any loss. There is no penalty to virtue; no penalty to wisdom; they are proper additions of being. In a virtuous action, I properly am; in a virtuous act, I add to the world; I plant into deserts conquered from Chaos and Nothing, and see the darkness receding on the limits of the horizon. There can be no excess to love; none to knowledge; none to beauty, when these attributes are considered in the purest sense. The soul refuses limits, and always affirms an Optimism, never a Pessimism.
His life is a progress, and not a station. His instinct is trust. Our instinct uses "more" and "less" in application to man, of the presence of the soul, and not of its absence; the brave man is greater than the coward; the true, the benevolent, the wise, is more a man, and not less, than the fool and knave. There is no tax on the good of virtue; for that is the incoming of God himself, or absolute existence, without any comparative. Material good has its tax, and if it came without desert or sweat, has no root in me, and the next wind will blow it away. But all the good of nature is the soul's, and may be had, if paid for in nature's lawful coin, that is, by labor which the heart and the head allow. I no longer wish to meet a good I do not earn, for example, to find a pot of buried gold, knowing that it brings with it new burdens. I do not wish more external goods, — neither possessions, nor honors, nor powers, nor persons. The gain is apparent; the tax is certain. But there is no tax on the knowledge that the compensation exists, and that it is not desirable to dig up treasure. Herein I rejoice with a serene eternal peace. I contract the boundaries of possible mischief. I learn the wisdom of St. Bernard, — "Nothing can work me damage except myself; the harm that I sustain I carry about with me, and never am a real sufferer but by my own fault."