 The great 20th-century Kabbalist Yehuda Ashlag viewed the terms "Jews" and "Gentile" as different levels of perception, available to every human soul.David Halperin argues that the collapse of Kabbalah's influence among Western European Jews over the course of the 17th and 18th century was a result of the cognitive dissonance they experienced between the negative perception of Gentiles found in some exponents of Kabbalah, and their own positive dealings with non-Jews, which were rapidly expanding and improving during this period due to the influence of the Enlightenment.However, a number of renowned Kabbalists claimed the exact opposite, stressing universality of all human souls and providing universal interpretations of the Kabbalistic tradition, including its Lurianic version.