Philosophers have long talked about two different kinds of pleasure: hedonic pleasure gained through good food and drink and eudaimonic pleasure gained from serving the common good. Researchers have discovered that the two kinds of pleasure have different biological consequences. Hedonic pleasure leads to a gene expression associated with inflammation that can cause arthritis and heart disease. Eudaimonic pleasure has the opposite effect: it reduces the stress associated with inflammation. Hedonic pleasure may be the emotional equivalent of empty calories: it offers short-term pleasure with long-term ill effects (ScienceDaily.com, July 29).