Victor Haghani’s maths proof that stock-pickers will hate

‘Risk matters hypothesis’ extends Bogle’s case for passive investing

Victor Haghani wants to talk about what he calls the “risk matters hypothesis”. It’s a project he describes as his most exciting in years, even though others, he says, might consider it a statement of the obvious.

The work – a series of mathematical proofs conceived as a conceptual sibling to John Bogle’s ‘cost matters hypothesis’ – crystallises a simple observation, but one that’s arguably been overlooked.

Haghani and his fellow researchers show that the average active investor inescapably takes