Supposedly, the three most beautiful words in the language are: "I love you." Hallmark card company has made billions by printing them on card stock and shaming men into buying them on Valentine's day.
I have a male friend who more than a decade ago told me the four most frightening words in the English language for a man to hear are: "I am not happy." The man knew that upon hearing those words, that the days to follow were sure to be unpleasant and expensive.
Now there's a study. And the Eagle Forum's Phyllis Schafly has explained it all here. Keep 'em barefoot and pregnant boys!