The Swiss have a well-deserved reputation for quiet efficiency and deadly dullness. Yet the nation consistently ranks among the happiest in the world. Are the Swiss on to something? Yes. For starters, nearly everything there functions exceedingly well. The trains do run on time. The Swiss, in other words, subscribe to philosopher Arthur Schopenhauer’s definition of happiness as ‘‘an absence of misery.’’ Then there is Swiss democracy. The Swiss vote on time and often ... very often. The average citizen might vote seven or eight times a year in various referenda, and at least one study has linked that kind of direct democracy with increased happiness. Finally, there is the biochemical explanation. Not drugs but chocolate. The Swiss consume large quantities, and chocolate contains tryptophan, a chemical that the brain uses to make the neurotransmitter serotonin, which creates a sense of well-being.