Commentary Our divided political environment has generated many charges of bigotry. One of the most important tasks is to define anti-Semitism. To accomplish this, I concentrate on both the group definition and the causes. Who Is Jewish? Jews are generally regarded as an ethnoreligious group or a spiritual version of an extended family in which members are related by blood and/or religion. Occasionally outsiders join, in which case the “adoption” is accomplished by conversion. Traditional Judaism recognizes the mother as the prime determinant of Jewishness, even if the individual adopts another faith or no faith. Liberal (“Reform”) Jews generally accept someone as Jewish if either parent is Jewish, but in the case of a Jewish father, the child must identify as Jewish. All traditions within Judaism allow conversion. Once converted, the convert remains Jewish even if the faith is abandoned later. The Bases of Anti-Semitism Overview. Every group, whether defined …