Missing Mona | Unknown, 1911

Proposal: The photo is displayed with its label underneath : "The Mona Lisa's vacant place in the Salon Carré, Louvre Museum, after having been stolen in 1911 | Picture taken by an anomymous photographer". Next to it, a sheet of paper with the following question and its three answer options written on it: "What is the work you see? 1. The photo 2. The absence of the Mona Lisa 3. This work."
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On August 21, 1911, the Mona Lisa was stolen from the Louvre. During her absence, there were more visitors to contemplate the empty space where the Mona Lisa was than ever before.
Who decides what constitutes a work of art?

Theft of the Mona Lisa painting | Unknown
Paris, L'Illustration, 2 september 1911, page 6