You can only tell if something has "worked" if you know what result you wanted; and the result you want depends greatly on whether you are left wing, right wing, conservative or liberal. Someone might think that a law and order policy worked because it resulted in lots of criminals being punished; someone else might think that it was a failure because there was no overall reduction in the amount of crime. You might think that schools sports policy worked because Team Little Britain won lots of medals in the Tokyo Olympics; I might think it was a failure because hardly any non-elite athletes were still taking exercise ten years after they left school.
The new American dictator said yesterday that he was in favour of torturing people because "torture works". It isn’t immediately clear what “works” means. Does it mean that if someone knows a secret they will definitely and automatically tell it to you provided you hurt them badly enough? Or does it just mean that if the goodies are doing some torturing, the baddies will stop doing so much terroristing? "If only we had been torturing people in the 1990s, the Twin Towers attack wouldn't have happened; once we started torturing people after 2001, the London bombing didn't happen. Or if it did, it would have been worse without the torture. Or it only happened because we weren't doing enough torturing. Or something."
Someone is said to have asked Auberon Waugh how a horrible person like him could possibly claim to be a Christian. "But if I wasn't a Christian" he replied "Think how much worse I would be."
There is nothing wrong with asking purely hypothetical questions; there is nothing wrong with thought experiments. "Don't be silly, I'm not on the moon" is not a very good answer to the question "If you dropped a feather and a one kilogram weight on the moon, which would hit the ground first? I suppose the ticking bomb fantasy establishes whether your objection to torture is a moral one, or a practical one: do you say "No, I wouldn't torture the guy, even if it totally would save the little'un life?" or "Yes, if in some magic way, torturing the guy would get my baby back, then I would torture him.".
But it occurred to me that the scenario we really needed to consider would be something like:
In these scenarios, it's always a Really Bad Guy who is getting tortured; not a basically pretty harmless guy who happens to know the codes. And one cannot escape the suspicion that when someone says "torture works" they are adding, under their breath "and even if it doesn't, the really bad guy had it coming to them." Torquemada, Matthew Hopkins and Donald Trump all know in advance that Jews, women and Muslims are "baddies", and the search for heretics, witches and terrorists provides a pretext to hurt bad people.
If your baby really was tied to a time bomb, and if you really did torture a terrorist, or a suspected terrorist, or a Brazilian electrician who looked as if he might be a terrorist, and if the guy holds out under torture; or tells you that they’re on Dantooine when they’re really on Yavin… and one way or another the bomb goes off and the baby dies…
If I saw some very powerful people actually looking at the dead baby, and saying "the baby is still alive", I would say that they were either mad or liars, and you would say that things weren't always as black and white as we Trotskyites like to pretend. You would write long think pieces in the Guardian about the interesting controversy of the exploding baby.
And years later, the story about the baby chained to the time bomb who saved by the torturing would be one of those things which everybody knows, like Alfred and the Cakes and the school that sang baa baa green street and weapons of mass destruction. Everyone would say that horrible as torture is and obviously we’re not in favour of it and it’s a great shame that we inadvertently castrated that kid whose dad had a name quite similar to the person who almost definitely knew something about an outrage that hadn’t actually happened yet...but you have to admit, torture stopped the baby from exploding.
Fortunately, no-one has attached any bombs to any babies. But my country is about to sacrifice its place in the world on a Quixotic whim. And it will be impossible ever to ask the question "Did Brexit work? Did it do what it was supposed to do?"
And if, by some chance, sanity prevails, we will have another 50 years in which people stare at big, yellow, curved bananas and say “of course, you aren’t allowed to buy curved bananas any more. It’s political correctness gone mad."
(It is just about possible to imagine the Remain camp, ten years down the line saying "well, that wasn't nearly as bad as we feared." It is impossible to imagine the Leave camp, even in the face of Armageddon, saying "We're afraid that didn't work as well as we'd hoped.")
We don't know what works, because the crazy people will see whatever they choose to see. But we know what is moral. What is right and wrong. Big people don’t hit little people. You can’t have sex with anyone without their consent. The rich help the poor. You don’t hurt other people, however much you might sometimes want to.
In a “post truth” world, that may be all there is to hold on to.