YouView - formerly known as Project Canvas - is a partnership between BT, the BBC, ITV, Five, Channel 4, Arqiva and TalkTalk.

BBC: Project Canvas to become YouView

The lack of certainty about Shakespeare makes him a blank canvas on which others can project their own emotions, and Dr Leahy says this can create very strong feelings if this identity is challenged.

BBC: Shakespeare scholars try to see off the Bard's doubters

The heroes of Mr Morton's book are the astronomers who yearn to solve Mars's scientific puzzles, the science-fiction writers who project their politics on to Mars's blank canvas, and the space-flight enthusiasts who dream of Martian colonies.

ECONOMIST: Mars