All of Judaism, and in many ways, all of Western tradition can be summed up in one sentence: Hear, O Israel, the Lord our God the Lord is One. The emphasis of this statement is: Oneness. Kabbalah teaches that this sentence summarizes the entire Torah and all of Western mysticism. This is the essential culmination of non-duality. It is not referring to the number one, for that would suggest that there are other numbers, or that there are no numbers (the idea of zero). This oneness is inclusive—transcending numbers—embracing all ideas, it holds within it nothingness as well as infinity. It is without limit. Kabbalah refers to this oneness as Ein Sof, which means “without end.” I usually refer to this as Boundlessness.