One might expect that an intelligent social species would devise cultural overrides to rein in potentially dangerous expansionist tendencies on a finite planet. Rather remarkably, the opposite is the case. One of the most important roots of overshoot is MTI society’s belief in human exceptionalism, the idea that H. sapiens is fundamentally different from other species. Exceptionalists posit that human individual and social behaviours are culturally rather than genetically determined; that human ingenuity can overcome resource scarcities; that we are not otherwise bound by the laws and limits of nature. The corresponding economic paradigm, neoliberal economics—which currently underpins global ‘development’—implicitly assumes that the economy and the ‘environment’ are separate systems, so that the former, propelled by continuous technological advances, can grow indefinitely, unconstrained by the latter. Hubristic nurture unabashedly reinforces expansionist nature.