In Baseline Scenario, James Kwak neatly discusses the implications of the science of happiness and that of behavioral economics on public policy.
It is an intriguing read, as he observes that the two seem to point us towards opposite directions. While behavioral economics tends to provide a basis for the state to get involved intimately with people's lives (i.e. finances, diet, fitness, sexual activities, vices, child-rearing to name but a few), the science of happiness supports the notion that besides guaranteeing a minimum standard of living, the state should take a back seat to churches and other forms of socio-civic engagements. That is because additional income above a minimum threshold does not increase happiness as much as human contact (among other things).
So rather than handing out tax cuts (that increase our incomes but do not necessarily improve our level of happiness), should the state be providing what behavioral economist Richard Thaler calls "nudges" to encourage greater social connections?
That would give both liberals and conservatives something to be both happy and sad about.