Hume’s Guillotine

David Hume saved up his money for a guillotine, but he was shocked to learn that shipping and handling were not included in the cost.
So, he borrowed a horse and cart from friends, and headed out to the craftsman to pick up his guillotine.
Despite having directions and a detailed map, he never did manage to find his way out to the craftsman’s.
“This is more difficult than going from ‘is’ to ‘ought’!” he whined.
The horse wondered how Hume managed to pay the craftsman in the first place, let alone submit the order.
But nobody listens to horses.