quixotic [kwɪkˈsɒtɪk] a.
1.) Caught up in the romance of noble deeds and the pursuit of unreachable goals; idealistic without regard to practicality.
2.) Capricious; impulsive (American Heritage Dictionary of the English Language).
Etymology: From English Quixote, a visionary, after Don Quixote, hero of a romance by Miguel de Cervantes.
"While the rubbing out of obscenities is the most self-conscious (and self-defeating) effort in Catcher, the very fantasy of being the 'catcher in the rye' is itself a notion of quixotic hopefulness" (J.D. Salinger, Harold Bloom (ed.), 2008).