Symmetry enters the depth-psychology corpus principally through McGilchrist’s sustained neurological and cosmological argument, where the term is carefully distinguished from its popular usage and pressed into service as a diagnostic for hemispheric pathology and ontological sterility. For McGilchrist, symmetry in its full mathematical sense — any operation that leaves a system unchanged — aligns with the left hemisphere’s preference for stasis, universality, and closed form. This alignment is not merely aesthetic: schizophrenic subjects exhibit compulsive symmetry-seeking (‘morbid geometrism’), while symmetry perception itself is paradoxically lateralized to the right hemisphere, which processes it globally. The deeper argument is ontological: symmetry is sterile, generative of nothing new, whereas asymmetry is fecund, cosmically prior, and constitutive of life itself. Yet McGilchrist resists a simple inversion — what is required is the dialectical pairing of symmetry and asymmetry, themselves an asymmetrical couple. Pauli’s contributions come from quantum physics, where symmetry classes govern the behavior of indistinguishable particles, and where violations of reflection symmetry (parity) proved experimentally shocking. Inwood’s Stoic materials deploy symmetry in a moral-psychological register, as the proper measure of impulse aligned with Right Reason. Pascal offers an aesthetic observation on symmetry’s perceptual grammar. Across these traditions, symmetry marks the border between the repeatable and the generative, the static and the living.