They only had so many horses at the race tracks, so they used to get the jockeys to race ponies in order to decide who got them for the race. The rest had to settle for zebras. But the zebras were untamed and not bred for racing, so the jockeys on zebras always lost. But since these were generally the weaker jockeys anyway, because they’d already lost on the ponies, the system worked out OK.

After a while though, it was decided this was unfair. Everyone involved in the management of the tracks thought that all the jockeys ought to get horses, regardless of ability. But they were still confronted with the problem of not having enough. They went through the books for hours and envisaged all sorts of permutations, but there was simply no way they could afford to give all the jockeys horses.

Until, one of the people involved in the management of the race track stood up and said: “well, how about we just paint the zebras, and call them horses? That way everyone would get a horse.”

“Of course! Perfect!” the management thought, and the next day they went and painted all the zebras brown, and told the jockeys they’d all be getting horses from now on.

“Fantastic news!” the jockeys thought. “This will be so much fairer from now on, we will all be competing on equal terms.” So they were all given their horses at random, and went off to compete in the race. But of course some of the horses were still zebras, and the jockeys on these horses struggled, and these were even some of the best jockeys at the track. But, because the zebras had all been painted to look identical to the horses, no one could work out why.