THE SUPPLY OF RAW MATERIALS
It was pointed out that growth cannot take place without favorable conditions in respect to a number of factors, including natural resources, labor power, capital, entrepreneurship, and advancing technology. These particular factors are basic for development. Other factors may prevent growth from reaching its potential; for example, insufficient purchasing power, economic instability, or unstable prices. Even though these conditions are favorable, an unfavorable condition with respect to the basic factors would militate against growth. For example, at any stage of technological advance, growth would be limited by the supply of natural resources, taken to include the metals and minerals, energy sources, water, agricultural products, and forests. It is important then to examine our prospects in relation to future supplies of raw materials. Later chapters will deal with the other factors. Conversely plentiful resources are encouraging. A new good source of raw materials can be counted on to increase investments in order to exploit it. This increased investment results in further growth of other industries as purchasing power expands.
Early economists pictured a dismal future for mankind because they thought that population increase would outrun the potential increase in food supply. This was based on the notion that little could be expected of the people in relation to restraining births whereas food supply could not be increased indefinitely because of the law of diminishing returns. Furthermore, relatively little progress was made in agricultural techniques so that it was hard to conceive of an improving technology that would be sufficient to overcome this tendency to diminishing returns. Although this early discussion was always in terms of the food supply, the same sort of reasoning could be applied to any resource and probably would have been if manufacturing had been more important. Thus man was thought to