I have just read a paper called “Political science, punditry, and the Corbyn problem’ by Peter Allen, a Reader in comparative politics at Bath. It reflects on how most pundits, including some political scientists, got Corbyn’s initial success and then survival completely wrong. I will not attempt to summarise the paper here. It is well worth reading. I am going to take it as read that many pundits did get Corbyn completely wrong in 2015 and 2017. This has nothing to do with whether the left ascendency is a good or bad thing, but just the failure of pundits to see why it was happening.