I like this one for two reasons:

• It shows the reason behind all of Epicurus’ efforts. So often called a “parasite” or denigrated for misunderstandings of his philosophy, the man felt that no philosophy was worth anything unless it helped people.
• It provides a nifty mechanism for dealing with what I like to think of as philosophy-speak. You might know what I mean — it is easy to find myself in company that likes to hear their own voice, and will use big words and complicated arguments to make me feel small and stupid. None of that matters unless the result is to make people happier.