The Perennial Philosophy — the doctrine that a single, universal wisdom underlies all religious and mystical traditions — occupies a contested but structurally central position in the depth-psychology corpus. Its principal advocates within these pages are Aldous Huxley, whose 1945 anthology gave the term its modern currency, Alan Watts, and the philosopher-religionist Huston Smith, each of whom is cited, debated, and sometimes tacitly assumed by mythographers such as Joseph Campbell. The tension the corpus most consistently registers is that between perennialist universalism — the view that mystical experience is everywhere the same at its core — and particularist or interpretivist critique, which insists that cultural specificity is not merely accidental dressing but constitutive of religious meaning. Daniel Noel’s editorial work on Campbell makes this fault-line explicit, locating it within a broader temperamental divide between those drawn to unity and those drawn to difference. Campbell himself occupies an ambiguous position: structurally perennialist in his monomyth thesis, yet evasive when pressed on the philosophical commitments that entails. Related contestations appear in the philosophy of mysticism, where Walter Stace, Gershom Scholem, and Steven Katz stake out irreconcilable positions on whether religious experience transcends its interpretive context. The Perennial Philosophy thus functions in this corpus less as a settled doctrine than as a productive provocation — the axis around which questions of universalism, myth, mysticism, and cultural difference perpetually revolve.