"It Takes Two To Speak The Truth"
Context: Thoreau in this part of his thoughts, first recorded during a river trip by boat in August and September of 1839, discusses "friendship," and many of the things that one's relationships to his fellow men mean. One of the most valuable services that friends perform is bringing out the best that one has: a man feels an obligation to be worthy of a genuine friend, and is stimulated to be more self-critical and scrupulous and to strive for higher and truer thoughts. Without the stimulus provided by close friends, a man tends to regress into intellectual and moral sluggishness.
. . . A Friend is one who incessantly pays us the compliment of expecting from us all the virtues, and who can appreciate them in us. It takes two to speak the truth–one to speak, and another to hear. How can one treat with magnanimity mere wood and stone? If we dealt only with the false and dishonest, we should at last forget how to speak truth. . . .