The light dapples on the grumpy waters of the River Thames and Jacob Rees-Mogg MP and I are nudging towards the end of afternoon tea alongside a terrace in the Houses of Parliament, when I raise the question of the leadership of the Conservative Party. In a matter of seconds the man nicknamed “the honourable member for the 18th century” unfurls from his chair and springs into action in the most contemporary of fashions: a smartphone is excavated from his pocket and a brief silence ensues as he scans his screen to clarify the issue that has sparked his curiosity.