Robert M. Adams, in his commentary on "Prose of the Seventeenth Century," state that Michel de Montaigne was the first essayist. What is an Essay? "Montaigne, in titling his writings Essais, emphasized the tentative and explorative nature of his though? (The Norton Anthology of English Literature. pg 1562) Adams writes, more generally, "that men were now trying out their selves in 'essays' (the world implies something tentative)" (Pg. 1556) Let us turn to the Oxford American Dictionary:
1) A composition, usually short and in prose, on any subject
2) An attempt
So in the meaning of the word, including in its use by the creator of the form, the notion of Final Truth is absent.