Futility: --Futility is the quality of having no useful result; uselessness. Lack of importance or purpose; frivolousness. A futile act. One will run into it a lot in existentialist writings, movies, art etc., and in real life situations.
He is useless on top of the ground; he ought to be be under it, inspiring the cabbages. --Mark Twain
A walking shadow, a poor player,
that struts and frets his hour upon the stage,
And then is heard no more. --William Shakespeare
The gods had condemned Sisyphus to ceaselessly rolling a rock to the top of a mountain, whence the stone would fall back of its own weight. They had thought with some reason that there is no more dreadful punishment than futile and hopeless labor. --Albert Camus
