Oops. Your first quote attributed to Twain has never actually been verified to be his (but I love it and never get tired of being reminded of it).
"This quote has been attributed to Mark Twain, but the attribution cannot be verified. The quote should not be regarded as authentic."
What is it that confers the noblest delight? What is that which swells a man's breast with pride above that which any other experience can bring to him? Discovery! To know that you are walking where none others have walked; that you are beholding what human eye has not see before; that you are breathing a virgin atmosphere. To give birth to an idea-an intellectual nugget, right under the dust of a field that many a brain-plow had gone over before. To be the first--that is the idea. To do something, say something, see something, before anybody else--these are the things that confer a pleasure compared with other pleasures are tame and commonplace, other ecstasies cheap and trivial. Lifetimes of ecstasy crowded into a single moment.
- Mark Twain, Innocents Abroad