Quixotic

Derived from Don Quixote, a novel by the Spanish author Cervantes, quixotic refers to an individual who easily becomes wrapped up in the romance of (what they believe to be) a noble cause, although their endeavours are usually futile or hopelessly unsuccessful.

The phrase 'tilting at windmills' can also describe quixotic activity, after the famous episode in Don Quixote where the protagonist attempts to joust with a group of windmills that he mistakes for evil giants.

The Impossible Dream is one of the most famous songs from the Broadway musical Man of La Mancha, based on the Cervantes book. The lyrics go:

To dream the impossible dream,

To fight the unbeatable foe,

This is my Quest to follow that star,

No matter how hopeless, no matter how far,