La Clé des champs (The Key to the Fields) by René Magritte, 1933.
This painting’s title is often translated The Door to Freedom. Magritte is playing with the same idea he uses in other paintings where he paints a picturesque window scene, complete with curtains, yet cunningly supported with easel legs. In those paintings, Magritte is telling you it that what you are looking at is, in fact, a painting of a window, not really a window.
Here Magritte has broken the glass of the façade to expose, exactly the same image on the other side. Again he is diminishing the significance of his own art by showing that the painting of nature is as mundane as the surrounding environment and the key to freedom is recognizing that fact.