nitwittedness

Her character, a properly brought-up young person who allows herself to become engaged to a twit, is supposed to be slightly silly, but Bonham Carter does not quite succeed in counterfeiting nitwittedness.

Shlepping his way overland from Philadelphia, he will be tricked by con men, be friended by a lonesome bank robber, roasted by the desert sun, frozen by mountain storms, captured by Indians, and from sea to shining sea, he will cause wise men to marvel at his unparalleled and in exhaustible nitwittedness.