“I learned this, at least, by my experiment; that if one advances confidently in the direction of his dreams, and endeavors to live the life which he has imagined, he will meet with a success unexpected in common hours..”

Commonly misquoted, converted to imperative mood, as "Go confidently in the direction of your dreams! Live the life you've imagined. As you simplify your life, the laws of the universe will be simpler".
Walden (1854)

Variant: Success is not measured by the position one has reached in life, rather by the obstacles one overcomes while trying to succeed
Source: 1900s, Up From Slavery (1901), Chapter II: Boyhood Days
Source: Up From Slavery: An Autobiography
Context: I have learned that success is to be measured not so much by the position that one has reached in life as by the obstacles which he has overcome while trying to succeed. Looked at from this standpoint, I almost reached the conclusion that often the Negro boy's birth and connection with an unpopular race is an advantage, so far as real life is concerned. With few exceptions, the Negro youth must work harder and must perform his tasks even better than a white youth in order to secure recognition. But out of the hard and unusual struggle through which he is compelled to pass, he gets a strength, a confidence, that one misses whose pathway is comparatively smooth by reason of birth and race.

"Experience" (1913) as translated by L. Spencer and S. Jost, in Walter Benjamin: Selected Writings, Vol. 1 (1996), p. 4

Original: (it) Scrive la pagina di ogni giorno della sua vita colui che ha il coraggio di vivere i propri sogni.
Source: prevale.net

'Excerpts from the Teaching of Hans Hofmann', p. 61
Search for the Real and Other Essays (1948)

Source: The Unbearable Lightness of Being

"Rome, 9 January"
Without Dogma (1891)