The Uncovered Head

What is it that has turned Jewish identity, the product of such a long history, into a problem that has been troubling the minds of Jewish thinkers and Hebrew authors for over two hundred years now? Is it true that the core and substance of Judaism is the Jewish religion? Is a religious Jew 'more Jewish' than a non-religious one? Is it the case that only the Orthodox have held the line, preserving the continuity of Judaism from its origins to the present day? If so, what is Reform Judaism? What