Environmental discussions often frame humanity in binary terms: either as steward of the Earth or as its principal ecological parasite. Contemporary evidence gives substantial force to the second description. Human expansion has reshaped mammalian diversity, converted habitats, degraded soils, altered climate, and accelerated extinction. This paper therefore begins by granting the strongest version of the counterfactual objection: many ecological indicators would plausibly be more intact today had Homo sapiens never exerted its historical influence. From that premise, however, it asks a narrower question. Does stewardship require that Earth be unable to function without humans, or only that humans possess a distinctive capacity to understand and deliberately alter ecological futures? The paper develops the concept of reflexive ecological agency to name a five-part capacity: causal reach, representation of ecological states, counterfactual foresight, evaluative recognition, and deliberate response or restraint. Empirical cases are used as constraints rather than proofs of a theological claim. Conservation meta-analysis shows that deliberate action can improve biodiversity relative to no-action counterfactuals, while the broken-window objection prevents repair of anthropogenic damage from being treated as evidence of net benefit. African and Amazonian dark earths, Indigenous fire stewardship, and Indigenous-managed lands provide stronger cases in which long-term human participation can sustain or create specified ecological functions relative to relevant unmanaged comparators. Tasmanian devil insurance populations and conservation of the volcanically threatened Montserrat oriole further show that human agency can respond to extinction threats that are not straightforwardly human-caused. Earth-system modelling establishes the magnitude, but not the moral value, of human geological power. Science cannot demonstrate that humanity was divinely appointed as khalifah. It can, however, show that stewardship is an empirically instantiated human capacity. Read alongside Islamic concepts of khalifah, amanah, taklif, islah, and fasad, this capacity is better interpreted as answerability attached to knowledge and power than as ecological privilege. Keywords: khalifah; environmental ethics; Islamic philosophy; Anthropocene; stewardship; reflexive ecological agency; counterfactual reasoning; conservation; extinction; soil; Indigenous knowledge