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Alternative forms 
Sisyphean (not comparable)
- Edith Wharton (1862–1937), The Torch-Bearer
- The Sisyphean load of little lives,\\Becomes the globe and sceptre of the great.
- 1959 — Leo Strauss, What Is Political Philosophy? and Other Studies
- In spite of its highness or nobility, it [philosophy] could appear as Sisyphean or ugly, when one contrasts its achievement with its goal.
- 2006 — Hannah Tucker, Entertainment Weekly, no. 888 (28 July), p. 50
- Rob Paulsen won an Emmy as the voice of Pinky, who was responsible for supporting Brain (Maurice LaMarche) in his Sisyphean quest for world domination...
- "How Life Imitates Chess" by Garry Kasparov, Bloomsbury USA publishing, 2007/2008: pg. 145 (Chapter 12, "The Inner Game"): "You can't overestimate the importance of psychology in chess, and as much as some players try to downplay it, I believe that winning requires a constant and strong psychology not just at the board but in every aspect of your life...It begins with intense preparation, which requires that you motivate yourself to work long, grueling, lonely hours. It often feels like a Sisyphean task, since you know that perhaps only ten percent of your analysis will ever see the light of day."
- (recurring but futile): like herding cats
Incessant or incessantly recurring, but futile