In his 1841 publication called Essays, Ralph Waldo Emerson includes an essay simply entitled Self-Reliance in which he states "Trust thyself…Great men have always done so and confided themselves childlike to the genius of their age…" .
Ralph Waldo Emerson was known first as an orator. Emerson converted many of his orations in to essays. A student of Emerson's essays will also want to study Emerson's since he often worked out in his journal entries ideas that later appear in his orations and essays.
Essays, First Series : Ralph Waldo Emerson - Internet Archive