With the Enlightenment begins what is considered the period of modern philosophy, a period that starts with a tabula rasa, returning to reason as the pure source of understanding – or so it is often argued. Ironically, by addressing the contributions of Jewish philosophers in terms of their “universal” significance, the conventional accounts, however, fail to attend to the specificity of modern Jewish thought, whose particular positioning challenges these very claims and universalist assumptions themselves. The critical significance of the trajectory of Jewish philosophers in the Enlightenment lies precisely in the way they use their particular perspective to examine reason's universalist claim. In so doing, Jewish philosophers have rethought, through reason, the very project of modern philosophy – a critical challenge that seems often lost in conventional accounts of philosophy in modernity. For while secularization is often seen as the condition of the new science and philosophy that emerge from the cultural rebirth in the Renaissance, this move to secularization reveals a selective blindness with regard to the contributions of Jewish philosophers curiously at odds with the period's claim to a universal scope. Though the middle ages had relegated Jews to a distinct if subaltern place of negative significance, modern universalism was no longer interested in a distinct Jewish difference when secularized post-Reformation Christianity had become the undisputed and single paradigm for spiritual and intellectual life.