The Anatomy Lesson: fame at 26 

The Dutch group portrait was a solved problem before Rembrandt touched it. A guild or a militia company pooled its money, each member paid a share, and each member expected a clear, well lit, unobstructed face. The result was usually a row of men behind a table, arranged by seniority, looking out at the viewer. It was a receipt as much as a painting.

In 1632 the Amsterdam surgeons' guild commissioned a portrait involving its praelector, Dr Nicolaes Tulp, a physician and public figure who would later serve as a burgomaster of the city. Public dissections were part ceremony and part civic theatre, staged in an anatomical theatre with paying spectators, and there was already a tradition of painting them. Rembrandt was twenty six, newly arrived, and had never handled a commission on this scale.

He did not paint a row. He built a scene. The dissected body of the executed criminal lies diagonally across the foreground, pale and foreshortened, taking up more of the canvas than any of the living men. Tulp sits calmly at the right, forceps in one hand, lifting the tendons of the forearm while his other hand makes the gesture of explanation. The seven guild members lean in around the head of the corpse in a tight, unstable pyramid, and no two of them are doing the same thing. One stares at the arm. One checks the anatomical text. One looks straight out, as if catching your eye at a lecture you arrived late to.

Every man is still recognisable, which is what the guild paid for. But the picture is about the moment, not the membership. The light comes from the upper left and falls hardest on the corpse and on the collars, so the composition reads as a single bright event surrounded by attentive darkness. You do not scan the faces one by one. You follow the demonstration.

It also flatters the sitters more cleverly than a straight row could. This is not a group of men who paid to be painted. It is a group of men caught in the middle of understanding something, which is exactly how a guild of surgeons wished to be seen in a city that had recently decided science was prestigious.

The commission worked. Within a few years Rembrandt had more portrait work than he could comfortably handle, a studio full of paying pupils, and prices at the top of the Amsterdam market. He was the painter you hired when you wanted to look like a person of consequence.

The next thing he acquired was a wife whose family connections mattered almost as much as her face, and he painted her more often than he painted any client.