Within the depth-psychology corpus, ‘planet’ occupies a densely layered conceptual space, functioning simultaneously as cosmological object, archetypal symbol, and psychological principle. The term’s ancient Greek root — planetes, ‘wanderer’ — anchors its earliest appearance in the literature as a descriptor for the seven visible celestial bodies organized hierarchically around the geocentric earth, a structure elaborated most fully in Plato’s Timaeus and its commentarial tradition. From that cosmological foundation, two major interpretive trajectories emerge. The first, represented with greatest sophistication by Richard Tarnas and Dane Rudhyar, treats planets as embodiments of archetypal principles that govern dimensions of human experience — not mere projections of mythological names onto inert matter, but intelligible correlates of psychic life observable in the constant coincidence between planetary alignments and corresponding events in human affairs. The second, represented by Arroyo, Sasportas, and Cunningham, treats planets as the primary alphabet of astrological practice: indicators of specific dimensions of experience that interact with signs, houses, and aspects to produce a dynamic map of the individual psyche. A persistent tension in the literature concerns ontological status — whether planets are symbols, forces, or gods — and this question connects the astrological corpus to its Platonic and Hermetic inheritance. The von Franz passages remind us that ‘planet’ also functions in depth psychology as literary symbol: the little prince’s journey through planets becomes a phenomenological map of shadow figures and adaptation.