Effective Altruism encourages people to choose effective ways of helping others.

One obstacle to achieving this goal is that acts of effective altruism are considered unkind – or at least, less kind than more ineffective altruism.

In a recent study, we asked over 16,000 people (in the US and the UK) to rate the cost, benefit and kindness of over 1,000 'everyday acts of kindness' (for family, friends, colleagues and strangers).

The acts included: sending someone an encouraging email, paying someone a compliment, holding the door open for someone, letting someone ahead of you in line, going grocery shopping for someone, talking to someone who is lonely, giving someone a lift to work, sending someone a bunch of flowers, buying someone lunch, doing home improvements for someone, sending money to effective charities, working to overturn a wrongful conviction, mentoring someone, saving someone from a burning building, adopting a child, and donating a kidney.

We found that the kindness of an act depended not only on how beneficial it was, but also on how costly it was. Holding benefit constant, costlier acts were considered kinder. This means that less efficient acts are considered kinder than more efficient acts. (These results hold even when controlling for the relationship the actor has with the recipient, and the country of residence.)

These findings are consistent with the theory that the function of altruism is to foster cooperative relationships with others. 

When choosing social partners, people pay attention not only to others' ability to create or acquire resources (sometimes called ‘competence’ or 'productivity'), but also to the proportion of those resources they are willing to give to you (sometimes called ‘kindness' or 'warmth'). And in fact, of the two criteria, people place a greater weight on kindness because it is a better predictor of the long-term benefits of a relationship. The key point is that whereas competence can be displayed and assessed by benefit alone, kindness is displayed and assessed by both benefit and cost. Hence the positive relationship between cost and kindness.

These findings are also consistent with a large body of empirical work showing that, when it comes to prosocial behaviour, people focus on the costs people pay, while neglecting the benefits they provide. 

All told, the positive relationship between cost and kindness raises a problem for effective altruism. If inefficient acts of kindness are better at fostering mutually-beneficial cooperative relationships with others – ‘winning friends and influencing people’ – then those performing efficient acts will win fewer friends, and influence fewer people. And as a result, they may find effective altruism less rewarding, and less sustainable. 

One possible solution to this problem would be to identify ‘outlier’ acts of kindness, that are considered kind despite their efficiency. Perhaps the cost of some acts are routinely over-estimated; perhaps some low-cost acts can be repeated more frequently; perhaps acts performed publicly differ from those performed privately. Isolating and explaining these type of acts could help us find the optimal trade-off, the ‘sweet spot’, between effectiveness and kindness.

Further research on the psychology of kindness will illuminate the relationship between cost, benefit and kindness, and help bring head and heart closer together.