Limits of Reason (German: Grenzen des Verstandes) is a 1927 painting by Paul Klee (1879-1940).

The Limits of Reason was first exhibited in 1926 in Rudolf Probst's Galerie Neue Kunst Fides in Dresden, along with 99 other tempera/water colors by Klee.

The static nature of the perfect red sphere which appears frozen and floating in space, in the white primed canvas of the upper part of the painting, contrasts with the dynamic complicated filigree linear structure of the lower part of the painting.

Crevel described a ladder, or a set of stairs, lost in red ether, as the only means of us to take a leap into the impossible, to jump so high, as if on a trampoline, and to latch onto the moon... "cette échelle rouge perdue au sein de l'éther tourterelle.

Cette échelle, voilà bien l'escalier, le seul qui puisse nous mener jusqu'au tremplin d'où nous sauterons, à pieds joints, dans l'impossible, puisqu'il s'agit enfin de décrocher la lune."

[3] In 2006/07, the Hungarian composer and pianist Andor Losonczy (1932-2018) created a piece with the same name as the 1927 painting, Grenzen des Verstandes, as part of this Klee project.