Reciprocity

Reciprocity is the urge to give something back when someone gives you something first. A favor, a gift or even a small kindness leaves a feeling of debt, and most people want to clear it.

In a store, there is usually only one way to clear it: buy. That is why so many sales begin with something free, from a sample at the counter to a salesperson’s extra half hour. The gift is small. The purchase that repays it often is not, and it can be the first link in a longer chain.

The soft drink and the raffle tickets

In 1971 the psychologist Dennis Regan published a laboratory experiment in the Journal of Experimental Social Psychology. The men who took part believed they were in a study alongside another participant. In fact that second man was a confederate, a member of the research team playing a part.

Regan changed two things. First, he made the confederate seem more or less likable. Second, he varied a favor. Some participants got a soft drink that the confederate brought them without being asked. Others got a soft drink from the experimenter, and others got nothing at all.

Afterward the confederate asked each participant to buy some raffle tickets. Regan recorded how many tickets they bought and how much they liked the man selling them.

The favor worked. Men who had received the drink from the confederate liked him more and bought more of his raffle tickets. Making the confederate more or less likable had only a weak effect. And when Regan looked closely at the ratings, the link between the drink and the buying did not seem to run through liking. It seemed to come from pressure to repay, the sense that a favor received is a favor owed.

That sense already had a name. In 1960 the sociologist Alvin Gouldner had described “the norm of reciprocity” in the American Sociological Review, arguing that a moral rule to repay benefits is one of the universal parts of moral codes. He quoted the Finnish philosopher Edward Westermarck, who wrote that repaying a benefit is “probably everywhere, at least under certain circumstances, regarded as a duty.”

The mint with the check

In 2002 the researchers Strohmetz, Rind, Fisher and Lynn tested the idea in restaurants. In downtown Ithaca, New York, across 92 dining parties, a small piece of chocolate with the check raised the average tip from 15.1 percent to 17.8 percent of the bill.

At an upscale Italian-American restaurant in central New Jersey, one server tried four versions with 80 parties. Tips averaged 18.95 percent with no candy, 19.59 percent with one piece per diner and 21.62 percent with two. When she gave one piece, then turned back as she was leaving and offered each diner a second, tips reached 22.99 percent. That was the same candy as the two-piece version. Only her apparent generosity changed. The authors judged that reciprocity explained the results better than a good impression or a good mood.

Why a small gift feels like a debt

Gouldner’s answer is that repaying a benefit is a moral norm, shared so widely that it feels like a duty rather than a choice. Not repaying feels like breaking a rule.

Regan’s study adds that the pressure does not depend on liking the giver. You can feel you owe a stranger, or a salesperson you found pushy. The restaurant studies add a third point: how generous a gesture seems matters, not only its size. A favor that looks personal and unplanned pulls harder than the same gift handed over as routine.

How a free favor fills a closet

Say a shoe store offers a free gait check and spends 40 minutes with you on a treadmill. You came to look. You leave with $120 running shoes, because walking out after all that help feels wrong. At home the new shoes make your old socks and shorts look tired, so you add $30 in running socks and a $50 jacket. A month later, a $60 watch to track your runs seems like the obvious next step. One free favor became $260 of spending, a clear case of the Diderot effect, where each new thing makes the next one feel necessary. The gift opened the chain. The obligation paid for the first link.

Where the free extras come with a bill

The first move, a gift, turns up in many places:

• Free samples. A taste at the counter costs the store little and makes walking past feel ungrateful. The zero-price effect makes the sample look better; reciprocity makes you want to repay it.
• Free consultations and fittings. A makeover, a fitting or a design session puts real time and attention in your hands before you have spent anything.
• Small personal gestures. The mint with the check, or a discount a clerk offers as something special just for you, is built to feel personal.
• Free trials. A trial offered as a favor works twice: you feel you owe the seller, and the endowment effect makes the thing feel like yours.
• Free upgrades and shipping. Extras framed as a favor create the same small debt. Our page on the Diderot effect in marketing shows how sellers use the free upgrade.

How to take a gift without owing a purchase

1. Separate the thanks from the sale. A thank-you repays a favor. A purchase is not owed. Say thanks, mean it, and treat buying as a separate question.
2. Decide before the freebie. Before a consultation, a fitting or a tasting, write down what you came to buy and your top price. If the answer is nothing, that stays the answer.
3. Ask the blank-slate question. Would you buy this from someone who had given you nothing? If not, the gift is doing the deciding.
4. Wait after any favor. For anything you want right after a free extra, wait a day. For bigger items, use the 30-day rule.
5. Total the chain. Before adding matching pieces, run the first purchase and everything it seems to need through the Chain Cost Calculator.

When paying it back is fair

Returning favors is how good relationships work, and there is nothing wrong with feeling the pull. When a server takes real care of your table, a tip is fair. When a small shop fixes a problem for free, a repeat visit or an honest review is a fair way to say thanks.

The test is who you are repaying, and for what. Are you paying a person back for help you actually received, or paying a company for a gesture designed to make you feel you owe it? If it is the first, give back gladly. If it is the second, a thank-you settles the account.