as the general rate of growth, or even if materials

production declined. A given rate of extraction of a

given materials mix can accommodate various levels of

production given appropriate technological changes.

A piece of material may be made to serve more complex

and useful ends, or a smaller amount of material might

be used to produce a given product. A piece of iron

might be made into a simple nail or into a part for an

intricate instrument. Copper might be used to form a

cuspidor or a computer component. In essence, more

value might be added per unit of material, or changes

in technology might lower materials needs per unit of

output.

 Either event would make increases in output

compatible with a fixed rate of materials extraction,

or constant levels of output compatible with reduced

extraction. However, technological changes which

lower resource needs relative to the value of final

products also free human and capital resources for

other kinds of productive activities. Those activities

might, in turn, make new demands upon resources at a

rate consistent with the new state of technology.

Hence, technology that encourages the more efficient use

of materials and more processing per unit of material

need not reduce overall materials requirements greatly.

As freed labor and capital become available for other