The concept of Relation occupies a position of striking philosophical weight across the depth-psychology corpus, moving well beyond its grammatical or logical senses to claim ontological primacy. Simondon provides the most radical formulation: relation is not a rapport between pre-constituted terms but a modality of being itself, simultaneous with and constitutive of the terms it appears to connect. This ontological revaluation displaces the Aristotelian categorical treatment, wherein Relation appears as a derived, outward-looking genus subordinate to Substance—a position Plotinus both inherits and interrogates, noting that relation is ‘not self-pivoted, but looks outward,’ and therefore cannot rank among primary genera. Palamas, working within a theological framework, restricts relational predication to God’s creative and filial activity, preserving divine simplicity against compositional corruption. Heidegger’s passing treatment links relation to truth as adaequatio, while insisting that not every relation constitutes agreement. Benveniste contributes a semiotic and ethnolinguistic register, tracing structural relations in kinship nomenclature and sign systems. What unifies these divergent approaches is a shared anxiety about whether relation is derived from terms or productive of them—whether the individual, the sign, the deity, or the judging mind can be grasped relationally without being dissolved into pure relativity. The tension between substantialism and relationism runs as a deep current throughout the corpus, making Relation a site of perennial theoretical contention.