Some people think that you can tell if someone is Jewish just by looking at their last name. Time and time again we've proven them wrong, yet the notion is out there. There are "Jewish" last names.
So, for those who still think that's the case, try this on for size:
Dustin Hoffman. Terrific actor. Oscar winner. Hoffman. Jew.
Philip Seymour Hoffman. Terrific actor. Oscar winner. Hoffman. Not a Jew.
Philip's father is a German Protestant, mother an Irish Catholic. There is absolutely nothing Jewish about him, except that pseudo-Jewish last name.
Well, supposedly "Jewish" names like Hoffman, Zimmerman and even Goldman (anything ending with "man", really), as well as Fischer, Meyer, Koch, etc, are not exactly Jewish. They all come from German, and quite often have ethnic non-Jewish German roots. Just like in this case.
But that's alright. We don't mind all the goyim with pseudo-Jewish last names. It gives us more fodder for this website, doesn't it?