The original rule was "I before E, except after C, or when it rhymes with May, like neighbor or weigh." My mom's maiden name was an exception to this rule, so she always adds, "and my maiden name."

BTW, in German, you pronounce the syllable based on the placement of the second letter in the "E-I" combination. If it's "EI" it rhymes with I, and if it's "IE," it rhymes with E.

But people screw it up anyway. By German rules, Epstein should be pronounced Ep-Styne, not Ep-Steen.