Simply sign up to the Science myFT Digest -- delivered directly to your inbox. Of all the big ideas floating around — long-termism, degrowth, space colonisation and so on — is any quite as radical as ...

A number machine is a way of writing rules using a flow diagram. The equation \(3j - 6 = 9\) can be shown on a number machine by writing out the functions that have been applied to \(j\) in the order ...