In tonight’s BBC “Question Time” special, devoted to the Labour leadership election, the foundational myth of Corbynism was repeated again and again. It is that old favourite – “the stab in the back”.

Audience members who support Corbyn claimed that Labour were ahead in the polls until the resignations from the Shadow Cabinet. Owen Smith gently corrected them – in 89 polls Labour were behind in 85 and level pegging in four. Rather than concede the point, Corbyn played to his support and repeated their lie, adding that hostile media coverage was also to blame for poor polls.

This was the pattern throughout the debate: Smith answering questions clearly and punchily, talking through the camera to the country; Corbyn basking in adulation and talking in generalities.