81:6.8

3. Scientific knowledge. The material aspects of civilization must always await the accumulation of scientific data. It was a long time after the discovery of the bow and arrow and the utilization of animals for power purposes before man learned how to harness wind and water, to be followed by the employment of steam and electricity. But slowly the tools of civilization improved. Weaving, pottery, the domestication of animals, and metalworking were followed by an age of writing and printing.