There are many definitions of art. An earlier definition described an artist as one who mimics nature. At one point in history that was true. Many artists have devoted their lives to perfectly emulating what they see. With beautiful, accurate landscapes and portraits so real looking, you might consider asking the people in them to stop staring at you, it is hard not to be amazed in the skill of a realistic painter, but is reality the same as perception? The answer has been proven over and over again to be no. If four people can have four different stories after an argument, how can we say that perception is reality? Retellings of individual experiences can be thorough, but rarely do they completely parallel true reality. The pipe is not a pipe. It is just what the artist saw, not a real object. You can't smoke out of it.
Houses at Auvers is what Van Gogh saw and felt. His experience and perception of this town was probably very different from what the natives saw. Van Gogh was very mentally ill and he killed himself the year he painted this work. I'm sure the roofs weren't all wavy like they were being viewed with teary eyes. I know the person was much more detailed than a few lines. Van Gogh was suicidal and sick and this is where he was. His eyes worked with his heart and his mind to show the world what Auvers looked like to him and him only. This is a pretty, colorful landscape of a French village, but it is also a landscape of Van Gogh's troubled mind. "This is not a village." This is what Van Gogh Saw.