The Education–Sustainability Paradox: Asymmetric Effects of Human Capital Expansion on Social and Environmental Sustainable Development Goas

The proposition that expanding education uniformly advances the 2030 Agenda has acquired the status of settled consensus — embedded in SDG 4, amplified by UNESCO, and routinely invoked in national development strategies. This paper shows that the consensus is empirically half-true. Using a balanced panel of 193 countries observed over 2000–2023, I estimate 96 two-way fixed-effects regressions connecting eight measures of education — spanning expenditure, enrolment, completion, attainment, and accumulated stock — to twelve Sustainable Development Goal outcomes. The estimates reveal a pronounced block asymmetry. On the social side, educational expansion is a first-order anti-poverty instrument: a one-standard-deviation increase in secondary enrolment is associated with a 0.16-log-point reduction in the $2.15/day extreme-poverty headcount and a 4.35-point reduction on the 0–100 SDG-1 composite, both significant at the 0.1% level. On the environmental side, the same treatment produces a β = +0.048 (p = 0.014) coefficient on production-based CO₂ per capita and a β = −0.260 (p = 0.031) coefficient on forest area — effects that are statistically significant but directionally perverse. Income inequality worsens rather than improves with schooling expansion (β = +0.71 on the Gini, p = 0.006). The asymmetry survives Driscoll–Kraay standard errors, Oster (2019) sensitivity bounds (δ > 1), and two-year lagged specifications. The findings qualify the optimistic narrative that frames education as "the key" to sustainable development: schooling is a central social block instrument, but cannot substitute for dedicated environmental policy. The 2030 architecture needs instrument–goal pairs, not universal keys.