"In reading Henry Thoreau's Journal, I am very sensible of the vigor of his constitution. That oaken strength which I noted whenever he walked or worked or surveyed wood lots, the same unhesitating hand with which a field-laborer accosts a piece of work which I should shun as a waste of strength, Henry shows in his literary task. He has muscle, & ventures on & performs tasks which I am forced to decline. In reading him, I find the same thoughts, the same spirit that is in me, but he takes a step beyond, & illustrates by excellent images that which I should have conveyed in a sleepy generality. 'Tis as if I went into a gymnasium, & saw youths leap, climb, & swing with a fource unapproachable, -- though their feats are only continuations of my initial grapplings & jumps."
- Ralph Waldo Emerson From Emerson's Journal, 24 June, 1863
 
"...a singular character -- a young man with much of wild original nature still remaining in him; and so far as he is sophisticated, it is in a way and method of his own"