Harry and Sophie wanted to take seriously the words the minister would utter as they exchanged rings: ‘These two lives are now joined in one unbroken circle.’ This meant putting their collective interest first, and their individual interests second. If they could do that, the marriage would be better for both of them.
But Harry had seen his own parents divorce and too many friends and relations hurt by betrayal and deceit to accept this unquestioningly. The calculating part of his brain reasoned that, if he put himself second, but Sophie put herself first, Sophie would get a good deal from the marriage but he wouldn’t. In other words, he risked being taken for a mug if he romantically failed to protect his own self interest.
Sophie had similar thoughts. They had even discussed the problem and agreed that they really would not be egotistical in the marriage. But neither could be sure the other would keep their part of the bargain, so the safest course of action for both was to secretly look out for themselves. That inevitably meant the marriage would not be as good as it could have been. But surely it was the only rational course of action to take?
Something doesn’t sound right. Two people are trying rationally to decide what is in their best interests. If they both act in a certain way, the best outcome for both of them is assured. But if one acts differently, he secures all the advantage and the other is left worse off. And so, to insure against this happening, neither does what is best if both do it, and so both end up with an outcome which is worse than it could have been.
This is a form of problem known as the ‘prisoner’s dilemma’, after a well-known example concerning how two prisoners should plead. Prisoner’s dilemmas can occur when co-operation is required to achieve the best result, but neither party can guarantee the other will play ball. Hence the typical example involves prisoners kept in separate cells, unable to communicate. But the same problems can arise even for people who share the same bed. The fact is that people do secretly betray the trust of their partners, often undiscovered for years.
The dilemma reveals the limitations of the rational pursuit of self-interest. If we all individually decide to do what is best for each one of us, we may well all end up worse off than we could have been if we had co-operated. But to co-operate effectively, even if our motive for doing so is self-interest, we need to trust one another. And trust is not founded on rational arguments.
This is why Harry and Sophie’s dilemma is so poignant. Their capacity to trust has been eroded by their experience of betrayal and divorce. However, without this trust, their own relationship is more likely to be unsatisfactory, or even fail. Who can blame them for their scepticism though? Isn’t it perfectly rational? After all, it is not founded on anything other than a fair assessment of how people actually behave in modern marriages.
If there is a wider moral to this tale, perhaps it is that trust, though it involves a certain amount of non-rational risk-taking, is required to get the most out of life. It is true that if we trust others, we leave ourselves open to exploitation. But if we don’t, we close ourselves off from the possibilities for what is best in life. Harry and Sophie’s rational, safe strategy protects them from the worst their marriage can bring, but it also separates them from the best.
| 7. | When no one wins |
| 14. | Bank error in your favour |
| 60. | Do as I say, not as I do |
| 82. | The freeloader |