All a man's strength and all his weakness go to make up the authority of any particular opinion which he may utter. He is strong or weak with all his strength and weakness combined. If he is your friend, you may have to consider that he loves you, but perchance he also loves gingerbread.—Journal, 16 February 1854
And as for advice, the information floating in the atmosphere of society is an evanescent and unserviceable to him as gossamer for clubs of Hercules.—"Paradise (to be) Regained"
I doubt whether one can give or receive any very pertinent advice.—Journal, 27 December 1858
I have never known advise to be of use but in trivial and transient matters.—A Week on the Concord and Merrimack Rivers
I would thus from time to time take advice of the birds.—Journal, 12 May 1857
If you have built castles in the air, your work need not be lost; that is where they should be. Now put the foundations under them.—Walden
If you would convince a man that he does wrong, do right. But do not care to convince him. Men will believe what they see. Let them see.—Thoreau to H.G.O. Blake, 27 March 1848
Others give their advice, he gives his sympathy also.—"Thomas Carlyle and His Works"
Public opinion is a weak tyrant compared with our own private opinion. What a man thinks of himself, that it is which determines, or rather indicated, his fate.—Walden
Show me a man who consults his genius, and you have shown me a man who cannot be advised.—Journal, 27 December 1858