Shwartz and colleagues dismantle the assumption that greater biodiversity produces uniform psychological benefit. Their iconic finding is that perceived species richness often relates more strongly to well-being than measured richness, while nature relatedness and ecological knowledge substantially moderate the relation. The theoretical contribution is a differentiated account of human-biodiversity encounter in which ecological condition, perception and prior disposition interact rather than align automatically. Methodologically, bird, butterfly and plant richness and abundance are sampled across twenty-four urban gardens and compared with six hundred in-situ questionnaires measuring well-being, knowledge and affinity to nature. The conceptual operation is moderated relationality: no environmental quality acts independently of the subject’s capacities to recognise, interpret and value it. The wider bridge reaches environmental psychology, urban ecology, phenomenology and conservation planning. The work cautions against universal benefit models and suggests that biodiversity policy requires both habitat enhancement and forms of ecological education capable of expanding perceptual competence without reducing complex ecosystems to immediately pleasurable scenery.