Neroon said:
It was in a collection of essays that had been compiled into a regular series of books, the name of which escapes me right now. Much of it I think centered on the sense of wonder and exploration, asking "is this all I am? - hence, the tag "the human adventure begins".
I believe you're referring to "The Best of Trek" books. That particular one was re-collected in "The Best of the Best of Trek."