Its not really (or at all) a self help book. It's evolutionary theory.
In David Buss's massive cross cultural survey of mate preferances, he showed heartwarmingly , that No1 for both men and women was kindness.
It seems adaptive to signal virtue, the byproduct could be, as MLKjr said
'the arc of the moral universe is long, but it bends toward justice'
Definition of virtue is clearly important here!
Miller is best known for 'the mating mind' where he argues that human intelligence, creativity etc is analogous to the pea cocks tail, the result of run away sexual selection, rather than the result of natural selection.
Apologies if I've ever so slightly gone off topic again..