This is Heng (恆), the Chinese hexagram of Duration. Thunder (Zhen) sits above Wind (Xun): arousing movement above, gentle penetration below, both in constant motion without exhausting themselves. Ancient diviners saw this configuration as the secret of lasting power—not rigid permanence but sustained movement in consistent direction. The character 恆 depicts a heart and the moon, suggesting emotional constancy through phases and cycles. Cézanne's mountain embodies geological duration; his decades-long artistic commitment embodies human duration; the viaduct embodies engineered duration. Each persists through different means toward the same end: presence across time. Cézanne painted Mont Sainte-Victoire repeatedly throughout his career, studying the same mountain from different perspectives over decades. The enduring presence of the mountain and the man-made viaduct demonstrate persistence through time—the hexagram's theme of duration achieved through constancy of purpose rather than force. The Judgment text states: "Duration. Success. No blame. Perseverance furthers. It furthers one to have somewhere to go." Duration requires direction—not mere repetition but movement sustained over time toward purpose. Cézanne didn't paint Mont Sainte-Victoire once but returned obsessively, each painting deepening understanding through patient observation. Song Dynasty commentary notes that duration differs from stubbornness; true constancy adapts methods while maintaining aim, like wind and thunder that vary intensity but never cease entirely. The viaduct channels water's flow year after year, its arches standing precisely because they flex slightly under stress rather than resisting rigidly. The Image Text counsels: "Thunder and wind: the image of Duration. The superior person stands firm and does not change his direction." Direction provides the standard—constancy of purpose permits flexibility of approach. Cézanne pioneered new ways of seeing and painting, yet his direction remained fixed: to realize sensation before nature. In the I-Ching's sequence, Duration follows Influence: after mutual attraction creates movement (31), sustained constancy over time (32) becomes possible. The mountain will outlast the viaduct, the viaduct outlasts Cézanne, the paintings outlast their creator—each form of duration teaching that persistence, not permanence, marks what endures.