In Book Two, Section 2 of Rumi's Masnavi, the story of a man who mistakes a crooked hair over his eye for the new crescent moon illustrates how a minor personal distortion or illusion (wahm) can obscure objective truth. Umar, possessing clear spiritual vision, points out the man's error, demonstrating that a small defect in perception can block out the vast reality of the heavens. This parable serves as a metaphor for how internal flaws, biases, and spiritual arrogance distort one's worldview and prevent one from seeing the divine truth.