Behind the Art: What makes ‘Portrait of Dr Gachet’ one of Van Gogh’s best works?

Every artist needs a muse. In Dutch painter Vincent van Gogh’s case it was his homeopathic doctor and artist Dr Paul-Ferdinand Gachet. In 1890, a few weeks before his death, the artist painted two portraits of Dr Gachet. The first version of the portrait was sold at an auction in 1990 for $82.5 million ($154.8 million today), making it the most expensive painting ever sold until Portrait of Adele Bloch-Bauer I by Gustav Klimt surpassed the…