Here’s a classic scene: a weary traveller walks through an airport. A flower is pushed into his hands by a religious adherent, who then hints that a contribution to the religious order would be welcome — but no obligation, of course, the flower was a gift.
Yet the traveller cannot shake the nagging guilt arising from reciprocity and begrudgingly throws some coins into a bowl.
Reciprocity is a powerful human instinct (see Robert Cialdini’s Influence for an entertaining discussion). I can only suppose, in the usual hand-wavy way one must when such situations arise, that it favoured our ancestors. “Tit for tat” strategies have long been recognised as the “best” performers in many game theoretic situations. If you cooperate, everyone comes out ahead. So reciprocity would be inborn.
Now imagine this also-classic scene: a pretty young lady is sitting at a bar. A young man, full of confidence, walks up and offers to buy her a drink, which she accepts.
Does she “owe” the young man anything? It is a matter of political and social dispute whether, because of the sexual undertones, she does. If our analysis was purely concerned with reciprocity, then yes — she “owes”.
But what does she owe?
Here a strange thing occurs. If reciprocity is to mean anything, then the value of goods or services exchanged ought to be more or less “equal” in the eyes of the parties, or else it won’t happen.
But in a reciprocity situation, one party has placed the other under obligation. In a normal market exchange you can simply choose not to come to agreement; in a reciprocity scenario one party has already committed the pair to have some of transaction.
How to value the repayment? It seems to me to turn largely on each party’s marginal value for the original gift.
Say, for example, that the young man is poor. To him that purchased drink might represent a painful fraction of his weekly income. He probably expects that it is worth a high-value reciprocation — to the point that some men think they are “owed” sexual favours, after which things can go dreadfully wrong.
Contrariwise, to a wealthy man, the drink might merely be worth a brief conversation. He places less value on the drink, so he expects less reciprocation.
But the woman may not see it that way. If to her the drink is expensive, she may feel that a greater reciprocal obligation has been created than the man does.
Isn’t that odd? The reciprocating party has substituted their own valuation of the gift for the giver’s valuation. The only moves left are to reciprocate at one’s own valuation, to feel guilt by failing to reciprocate at one’s own valuation, or to refuse to accept the gift in the first place.
This might also explain why many couples where one partner is rich and the other isn’t may break up: the wealthy partner feels no sting at being generous, the poorer partner feels that they are under an ever-escalating obligation which cannot be repaid.
(Before you ask: no, I have not been cruising the bars buying drinks for young ladies — I’ve been reading essays by FA Hayek…)