How Many Jews Are in the World Today? Who is a Jew? Counting
Jews requires decisions about who is being counted, a direct
function of whom we define as a Jew: biology, self-identity, or
behavior. Biological Jews are individuals with a Jewish parent
versus those Jews who practice Judaism, with or without having a
Jewish mother or father. According to Reform Judaism and the
patrilineal descent of Abraham, Isaac and Jacob, a Jewish father
can define a Jew. According to Orthodox and Conservative Judaism
and the tradition of hundreds of years, only a Jewish mother
defines a Jew. Demographic surveys usually do not ask about
grandparents, although Israel‘s law of return includes
grandparent lineage. Self-identity is how individuals think of
who they are. Some people think of themselves as Jews regardless
of their parents‘ religion. They may have Jewish heritage or
Jewish peer groups. Behavior is what people do. Behavioral Jews
practice Judaism and live as Jews, with or without biological
origins. This includes peopl