Monet's Rouen Cathedral

Monet painted the facade of Rouen Cathedral over thirty times between 1892 and 1894, each canvas capturing the same stone surface under different lighting conditions. Morning light turned the stone pink and gold. Midday flattened it into blinding white. Dusk wrapped it in violet shadow.

The series proved that no object has a fixed visual identity. The cathedral was a different painting every hour because light itself was the subject. What seemed solid and permanent was actually in constant visual flux.