I came across this interesting story from the London Sunday Times talking about happiness. It is sort of long and technical but interesting reading.
I liked this part…
Can scientists tell us what happiness is?
Economists accept that if people describe themselves as happy, then
they are happy. However, psychologists differentiate between levels of
happiness. The most immediate type involves a feeling; pleasure or joy.
But sometimes happiness is a judgment that life is satisfying, and does
not imply an emotional state.
Public surveys measure what makes us happy. Marriage does, pets do,
but children don’t seem to (despite what we think). Youth and old age
are the happiest times. Money does not add much to happiness; in
Britain, incomes have trebled since 1950, but happiness has not
increased at all. The happiness of lottery winners returns to former
levels within a year. People disabled in an accident are likely to
become almost as happy again. For happiness levels are probably
genetic: identical twins are usually equally bubbly or grumpy.