
Until recently, having cultivated a lengthy white beard, Jon Lansman resembled a rather psychedelic Father Christmas. The now clean-shaven Momentum chair was, it transpires, in mourning.
“It was the death of my mother… I can’t remember whether it’s a Talmudic or biblical requirement [Lansman is Jewish]. I’m not religious, it’s a cultural thing, my dad did it for his parents, I think she would have liked it,” Lansman told me when we met recently for lunch at the Cellarium Café, a medieval undercroft adjacent to Westminster Abbey.