"No, no, you and Jennifer are fine. It's your kids, Marty, we have to do something about your kids — they're Jews!"

What makes someone a Jew?

Those of us of a more orthodox bent would say "their mother is Jewish" and leave it at that. But there's something so... exclusive about that definition. Are we really so numerous that we can simply ignore the large, dedicated Jewish communities that don't fit that neat little definition?

For instance, young Republican, time-traveler, stem-cell spokesperson and all out 80s hunk Michael J. Fox: married to a Jewish woman. Has four children, all of whom he is raising as Jews. Member of a Reform temple. Helps his kids with their Torah homework.

Does that sound like a Jew? It sure does to us. Yet is Fox Jewish by birth? By conversion? No. Does he have to be? What makes someone a Jew?

The answer we have always held onto is something a little more ethereal. If someone feels — in their heart of hearts — that they are Jewish, then they are. And that should be enough. Right?

OK, probably not. But if we had a DeLorean and flux capacitor, well, let's just say things might turn out a little differently.