Altruism and Blood Donation

Philosophers debate whether there is a such thing as true altruism, and interestingly, blood donation is an often-studied example. Altruism or selflessness differs from loyalty or duty in that one sacrifices something for another - often a stranger - with no expectation for compensation or benefits. Often, the act of giving is complemented by a feeling of personal gratification, and philosophers debate whether this internal satisfaction makes "true altruism" impossible.

Why do we do this? Doesn't the theory of evolution imply that we should look out for ourselves and our DNA rather than that of a stranger? We do seem to act in this way. Some studies show that kinship - as indicated by facial resemblance and similar names - increases trust and helping behaviors. Politicians take advantage of this by using kinship terms to increase buy-in from their audience. It makes sense that we'd protect our children or relatives, but why sacrifice our time, energy, and possessions on the welfare of someone completely unrelated?

Perhaps for complete strangers, altruism persists because helping others - even strangers - may be better for the group as a whole. Sometimes, we expect reciprocity in altruism; we aid victims of natural disasters hoping that someone would give us aid had that befallen us. And some people are generous to cultivate that reputation of generosity; publically announcing donations increases the size and frequency of those donations.

So why do we donate blood? Say a blood donation involves no material benefit; you don't get cookies or a sticker or even acknowledgement. You don't know who your blood will go to, or even if it will be used at all; perhaps your blood will simply sit in the blood bank until it expires. Even in these austere circumstances, some people will be donors. Why? Even if there's nothing in it for them, and even if they don't know if any good will come from it, they are still willing to sacrifice something. Philosophers examine questions like these in hopes that it will elucidate more about human nature.

Image of Jacques Louis-David's Belisarius Asking for Alms is in the public domain.