Only when the last tree is cut, only when the last river is polluted, only when the last fish is caught, will they realize that you can’t eat money.

The saying is a warning about ecological limits and the folly of valuing wealth over the natural systems that sustain life. Its structure—repeating “only when the last…”—frames environmental destruction as a one-way progression toward irreversible loss, culminating in a blunt economic truth: money cannot substitute for food, clean water, or functioning ecosystems. The line critiques short-term profit and extractive practices, suggesting that recognition of nature’s value often comes too late, after collapse. In modern usage it functions as an environmentalist maxim, urging stewardship and a rethinking of “prosperity” to include the health of land, rivers, and wildlife rather than financial accumulation alone.