The Anatomy Lesson of Dr. Nicolaes Tulp is a 1632 oil painting on canvas by Rembrandt housed in the Mauritshuis museum in The Hague, the Netherlands. Dr. Nicolaes Tulp is pictured explaining the musculature of the arm to medical professionals. Some of the spectators are various doctors who paid commissions to be included in the painting. The painting is signed in the top-left hand corner Rembrandt. This may be the first instance of Rembrandt signing a painting with his forename (in its original form) as opposed to the monogramme RHL (Rembrandt Harmenszoon of Leiden), and is thus a sign of his growing artistic confidence.

It is believed that the actual event in the picture can be dated to January 31, 1632. The Amsterdam Guild of Surgeons, of which Tulp was the official City Anatomist, was permitted one public dissection a year. It would be performed on the body for an executed criminal. In this case, the corpse was that of the criminal Aris Kindt (alias of Adriaan Adriaanszoon), who was convicted for armed robbery and sentenced to death by hanging.

In the 17th century, anatomy lessons were a social event taking place in lecture rooms that were actual theaters, with students, colleagues and the general public being permitted to attend on payment of an entrance fee.

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