134

 On the other hand in recent weeks, some author-

itative voices have predicted disaster:

 If the present growth trends in world population,
 industrialization, pollution, food production, and
 resource depletion continue unchanged, the limits
 to growth on this planet will be reached sometime
 within the next one hundred years. The most probable
 result will be a sudden and uncontrollable decline
 in both population and industrial capacity.(10)

 Five years ago, except for one or two writers in

the United States, this last gloomy prediction could well

have been interpreted as a kind of "traison des clercs,"

an unmitigated heresy.

 The optimism of Barnett and Morse rests upon

theory backed by empirical evidence. In their view,

resources are not simply physical quantities, but

processes; they can grow through technological change;

as Zimmerman said long ago: they are not, they become.11

A body of material too lean or too distant to be used

as a resource at one time may be made relatively richer

through innovation or as a result of changing economic
 12
conditions, including increased price.2 Either

occurrence could effectively increase resources even

though no change occurred in a physical sense. Further,


 1Dennis L. Meadows et al., The Limits to Growth
(New York: Universe Books, 1972), p. 23.

 E1Erich W. Zimmerman has been one of the major
exponents of this view. Cf. Zimmerman, World Resources.

 12Increased price makes sub-marginal deposits
worth mining.