Edvard Munch, the 20th-century artist who brought us The Scream, was haunted by an anxiety and restlessness that extended to his art, where it was expressed as an obsession with newness, the need to push his art beyond boundaries. Two giants in their fields, the Scottish painter Peter Doig and the Norwegian author Karl Ove Knausgård, explore the challenge of transcending the norms in their own work, using Munch as a touchstone. —J.V.