Anyone who regularly reads the financial papers or business weeklies would conclude that the world is in reasonably good shape and that long-term economic trends are promising. Even those predicting a severe global recession in 1991 are bullish about the longer term economic prospects for the nineties. Yet on the environmental front, the situation could hardly be worse. Anyone who regularly reads scientific journals has to be concerned with the earth's changing physical condition.
Economists interpret and analyze trends in terms of savings, investment, and growth.
They are guided largely by economic theory and indicators, seeing the future more or less as an extrapolation of the recent past. Advancing technology, economists believe, can push back any limits. Their view prevails in the worlds of industry and finance, and in national governments and international development agencies. In contrast, ecologists study the relationship of living things with each other and their environments. They see growth in terms of S-shaped curves, a concept commonly illustrated in high school biology classes by introducing a few algae into a petri dish.