Both.

So someone with Jewish ancestry that is a practicing Catholic, and someone that is not of Jewish ancestry that converted to Judaism are both Jewish? That sort of makes it an ambiguous term, no? What if someone was born to two parents that are not of Jewish ancestry, but converted to Judaism? Is that person a Jew by birth? What if that person becomes a Buddhist later in life? Are they still a Jew?

>So someone with Jewish ancestry that is a practicing Catholic, and someone that is not of Jewish ancestry that converted to Judaism are both Jewish?

If your mother is Jewish, then the Jewish establishment would consider you Jewish. You are considered Jewish if you convert.

>That sort of makes it an ambiguous term, no? Unlike other religions, Judaism is a religion and a cultural identity. Many Jews are secular, but still have strong cultural connections.

>What if someone was born to two parents that are not of Jewish ancestry, but converted to Judaism? Is that person a Jew by birth?

That person is not a Jew by birth, but that person is a Jew by conversion.

Historically, the only real test of "Jewness" that matters is this: if the Nazis were around, would they want to kill you?

> Historically, the only real test of "Jewness" that matters is this: if the Nazis were around, would they want to kill you?

It seems sorta sad if that's what the Jewish community uses as an 'Are you a Jew?' litmus test.

>It seems sorta sad if that's what the Jewish community uses as an 'Are you a Jew?' litmus test.

Sad? It's survival. (And yes, it is sad that antisemitism exists.)

Survival? Where are Jews hunted nowadays?

I'm talking about what the Jewish community currently uses. It seems sorta sad that they would adopt the same attitude toward 'Jew-ness' that the Nazis used... In a Helsinki-syndrome sort of way.

If the world were perfect then no one would have to be paranoid.

The Helsinki syndrome has nothing to do with this.

>Stockholm syndrome is a psychological response sometimes seen in abducted hostages, in which the hostage shows signs of loyalty to the hostage-taker, regardless of the danger or risk in which they have been placed. [http://en.wikipedia.org/wiki/Stockholm_syndrome]

My bad, meant Stockholm

Indeed it makes the term ambiguous, but luckily in this case its easier to fix. When it matters, then just specify: If you are saying "Jews believe that..." you are referring to people who practice Judaism. If you are saying "Jewish genes are such that..." you are referring to someone of Jewish ancestry.

I suppose it could be more confusing with people of mixed ancestry, but we can probably generally find a usable definition by context.