Might a painting ever achieve the veracity of a sculpture, a "real" object in space that we can walk around and view from every angle? Could the documentary quality of an engraving ever be equalled by a painting? And how could painting respond to photography – drawing with light – an invention that in the 19th century prompted a thorough reconsideration of painting’s purpose.

Some 50 portraits by Paul Cézanne – almost a third of all those the artist painted that have survived – are on view in this quietly sensational exhibition. Eye-opening and heart-breaking, it examines his art exclusively in the context of his portrayal of people for the first time.

Born into an artistic Swedish-speaking household in Helsinki, Tove Jansson’s first, and most enduring, ambition was to be a painter. Although best known as the illustrator behind the creatures of Moominvalley, those plump white hippopotamus-like folk with an existential longing for adventure, Jansson came to regard her widely successful creations as a distraction from what she considered to be her “real work”.

This is the latest in a line of beautifully curated, closely focused exhibitions that the Courtauld Gallery does so well. Its subject is the great Russian-French painter Chaim Soutine (1893-1943) who, remarkably, has not had a UK exhibition devoted to his work for 35 years.

During his time at the Slade David Bomberg — the subject of a major new retrospective at Pallant House Gallery — was described as a "disturbing influence". The fifth son of Polish-Jewish parents who fled the pogroms, he grew up at the turn of the 20th century in the East End of London where neighbours lived on top of one another and space was scarce.

The Kabakovs' exhibition made me thank my lucky stars I was not born in the Soviet Union. A recurring theme of their work is the desire to escape – from the hunger and poverty caused by incompetence and poor planning, and the doublethink required to survive under a regime that became ever more repressive the greater and more obvious its failings.

There's something here for everyone, as a "roll up!" slogan for one of the greatest shows in town might put it.

The best way to see Marc Quinn’s exhibition at Sir John Soane's Museum is to begin at the end, in a room explaining the process of casting the sculptures’ moulds from the entwined bodies of him and his partner, dancer Jenny Bastet.

The Royal Academy has a winning line in spectacular exhibitions that have become essentials in London, theatrically and dramatically revelatory presentations in themselves. Here is another winner, the American star Jasper Johns, a collaboration with the world’s newest gallery of contemporary art, the Broad in Los Angeles.

Beautiful, shy, charming and talented, Jean-Michel Basquiat was a shining star who streaked across the New York skyline for a few brief years in the early 1980s before a heroin overdose claimed his life at the age of only 27.