Part 13 · Chapter 110

But the skin of the skull itself, in which the hairs grow, is a bare part, without hair, and it is white — like the white paper upon which black letters are written and inscribed with ink, while the whiteness of the paper remains between each letter and the next; and the writing is black fire upon white fire. Likewise in this skull, the hairs are the letters, and the skin of the skull is the whiteness of the paper. Therefore this skull is called the aspect of the bare place, the "white head," for it is this white skull of Arich Anpin that is plainly referred to in the Zohar as the "white head."