Nairobi, June 18 -- Who cares about legacy? Legacy, Mendi Njonjo suspects, is one of humanity's more flattering delusions - a hubristic little belief that we will be remembered, that history keeps careful, grateful records of our contributions. But history is a careless archivist. It forgets fast, and it forgets almost everyone. A century from now, nobody will know who built the bridge in Makueni, or who put 50 disadvantaged children through school in Rongo. The bridge will matter. The education will remain. The plaque never does.

"Once you accept the incontrovertible fact that we will all be forgotten," says Njonjo, Managing Director of the KCB Foundation, "the question becomes: what are we straining for?" The answer, she has decided, c...