In a finite world this means that the per capita share of the world’s goods must steadily decrease.

Garrett Hardin made this point in the context of late‑1960s debates about population growth, resource limits, and environmental degradation. Writing as an ecologist, he argued that because the Earth’s resources are finite, continued growth in population (or in aggregate consumption) inevitably reduces the amount of goods available per person unless growth is checked. The line reflects Hardin’s broader “limits” framework that culminated in his influential arguments about the “tragedy of the commons,” where individually rational behavior in using shared resources can collectively produce ruin. It was part of his case that technical fixes alone cannot solve problems rooted in population pressure and shared-resource incentives.

The sentence compresses a zero‑sum implication of ecological limits: if total goods are bounded while the number of claimants rises, average shares fall. Hardin uses this arithmetic to challenge optimistic assumptions that prosperity can expand indefinitely for everyone without restraint. The claim also functions rhetorically: it frames population growth as a distributive problem (who gets what) and a political problem (how societies decide limits), not merely a scientific one. Whether one accepts his conclusion depends on assumptions about what counts as “goods,” how technology changes effective resource limits, and how equitably goods are distributed; Hardin’s emphasis is that biophysical constraints ultimately force tradeoffs.