There are some questions that are persistently treated as though they were ethical, spiritual or philosophical when actually, they're just plain factual. "Does suffering improve us?" is one of them. There are some theoretical issues around what "improvement" and "suffering" mean, but the answer comes mostly not from intellectual reflection but empirical observation. And that answer seems to be a pretty unequivocal no.

Take psychic suffering first of all. Severe depression is one of the most acute forms of pain known to humanity. Those who have suffered from both depression and serious physical illness are almost unanimous in agreeing that the depression is worse. Does this make them better people? Certainly not at the time. I've seen depression close up with several people, and one of them hit the nail on the head when they said that depression makes you really selfish. You can see that it's taking its toll on people close to you, but you are just too self-absorbed to change how you treat them.

Are they better having come through the depression? I see no evidence for this, I'm afraid. It is often said that having gone through any kind of suffering tends to makes you appreciate life more and live more in the present. I'm not sure how universal or long-lasting these effects really are. I suspect that, as usual, The Simpsons gets it right. In one episode, Homer thinks he has 24 hours to live, but actually survives into the 25th. Jubilant, he declares, "From this day forward, I vow to live life to its fullest!" Over the credits, we see him back in front of the TV, his belly the only thing filled to its fullest.

But even if most people do appreciate life more, let's not confuse that with being a better person. Indeed, I can easily imagine someone coming through a health scare and saying, "I used to worry constantly about the world's poor and the the future of the planet. But you know what? Life's too short. Just savour each day. After all, the poor will always be with us, as the Good Lord said." It is good to appreciate every moment, but doing so doesn't make you good.

Think of other common forms of suffering and most of the time, you will see no evidence that it improves people at the time of suffering or afterwards and quite a lot that it makes them worse. Soldiers return from the horrors of the front line broken men and women. Someone goes into what becomes a terrible, traumatic relationship open to love and leaves it suspicious, more misanthropic and full of self-loathing. In areas of socio-economic suffering there is more crime and more violence. You'll need to point to a lot of examples where the suffering has a good effect to balance out the innumerable cases where it clearly doesn't.

Why then do so many persist with the idea that suffering is good for us? The religious need to, of course. If suffering is not, on balance, a good thing, then there can be no benevolent creator in charge of this show. But even without a theological motivation, the thought of so much suffering without redemption can be almost intolerable. Believing it has a point can be the only way to make life bearable.

If human weakness is one reason to persist with the myth, there is another, better one. Whether or not suffering does tend to improve us, we can ask whether it can improve us. And that depends on how we react to it. We can take suffering to be an opportunity to learn and to grow. But if we are honest, we should remember that this is making the best of a bad job, and that minimising suffering takes priority over optimising its outcome. "That which does not kill me makes me stronger" is not a law of the universe. What it can be, if we so choose, is a resolution.