The first difficulty is that, over the last one hundred and fifty years, the term 'Jew' has come to be used in two very different ways. To understand this, let's imagine ourselves back in 1780. At that time, the meaning of this term for everyone coincided with what the Jews themselves considered to be the constitutive basis of their own identity.
This identity was essentially religious; moreover, the precepts of religion governed, down to the smallest daily detail, all aspects of the social and private life of Jews amongst themselves and in their relations with non-Jews. It was unthinkable for a Jew to drink even a glass of water in a non-Jew's home.
This situation was changed by a twofold process, which began in Holland and England, continued in France during the Revolution and in the countries that followed its example, and eventually spread to the modern monarchical states of the nineteenth century: in all these countries, Jews acquired numerous and important individual rights (and, in some cases, complete legal equality); and the judicial power that the Jewish community exercised over its members was abolished. It should be noted that these two developments were simultaneous, and that the second - although little known - is even more important than the first.