The Ari, the greatest of the kabbalists, taught that the prerequisite for the creation of the cosmos was a complete and utter withdrawal of the primordial infinite light. Only then could a finite trickle of light return to generate and sustain a universe. All the light was withdrawn. There is no information, no revelation, no enlightenment, but for an infinitesimal afterglow attainable to those who toil for a lifetime. But the origin of light, the essential core of reality—that was never withdrawn. It is always accessible, everywhere, at all times, to all...