The gift of blood
 
I lived the early part of my life in Britain, emigrating to the U.S. when I was about 40. While in Britain I regularly donated blood. When I came to the United States I continued giving blood, but after two or three donations decided to stop. The experience was no longer a source of satisfaction to me. I’d like to explain why.
 
In The Gift Relationship: From Human Blood to Social Policy (1970, reissued 1997), Richard Titmuss described the voluntary donation of blood as 'institutionalized altruism':
 
[It] represents the relationship of giving between human beings in its purest form, because people give without the expectation that they will necessarily be given to in return.