SCIENCE IN MAN’S STRUGGLE ON ARID LANDS 27 
True, there are limits beyond which the use of renewable resources 
of soil, water, and vegetation cannot be intensified without 
trouble. Once we go beyond such limits it is always difficult and 
usually painful to restore their optimum use. Overgrazing of 
ranges, overcutting of forests, or excessive tillage on farm lands 
may initiate new cycles of erosion hard to control. Restoration of 
the soil may call for very difficult physical and social adjustments. 
The continued overdraft on the local ground water, using it faster 
than it recharges, can mean only reduced water some day and 
severe social penalties on someone. 
Such limits on resource use are only partly fixed in nature. They 
depend as well upon man’s skill, patience, and industry. Using 
the principles of science, we invent new tools of enormous power— 
in engineering, in biology, in soil and water management, and in 
administration; and we adapt them to local conditions. Even 
more important than the tools yet invented are the basic skills of 
science, the skills of basic research by which we get the principles 
for inventing still more. 
An attempt “‘to return to nature,’”’ to a way of life without tech- 
nology, would condemn the majority of the world’s population 
to starvation and death. This majority has learned in recent years 
that starvation is unnecessary. In fact, the present unrest in the 
world about food and opportunity is not due to material shortages 
in terms of the past. Never was there greater abundance. The 
unrest is due to a new realization of the enormous shortages we 
have in terms of what is possible with the full use of modern 
science. 
We are seeking a cultural balance or, more accurately, a cultural 
dynamic of relationship between resources and people for efficient 
sustained production. For this we use all the skills of science and 
engineering. The relationship we seek is hardly a balance, except 
perhaps momentarily along the way from one point of efficiency 
and abundance to a higher one. 
Where Do We Stand?2 
First, I shall review some of the basic aspects of arid land 
resources. 
