The Treachery of Images
There are different interpretations of the work. A common one says that with the painting, Magritte wanted to say that the thing was a painting, and not a pipe which can be smoked. The idea is similar to the word "dog". That word doesn't bark, or wag its tail, either. Michel Foucault also did an interpretation, in 1973. Foucault says that an image of an object is different from the object itself. Also, by showing something that looks like a paradox, Magritte forces the viewer to think about what the "reality" of an object really is.