favorable view of past changes projected optimistically into an indefinite future. The accumulation of scien tific knowledge implied future progress in scientific thought and there appeared good reason to believe that such knowledge was capable of indefinite advancement. The application of scientific knowledge in the form of 12 applied technology to the problems of physical existence could yield progress for the whole of mankind. Belief in the operation of fortune and the intervention of Providence came to be supplanted by the belief that man might determine his own destiny, or even that he might be acting only as a role-player in a deterministic system that would of its very nature yield constant progress. A rational, mechanical, technical view of man and his surroundings appeared and flourished even as the wonder of science laid bare the secrets of the physical world and as its counterpart, technology, improved the material lot of man. It is CtheJ dynamic character of technology that makes it so significant for the idea of progress. The latter assumes that mankind has been slowly advancing from a crude stage of primitive civili zation; the former demonstrates what can be accomplished by exhibiting its achievements and disclosing its working methods. What was once Utopian becomes actuality. What appears to be impossible may be surmounted. The ancient theory Our purposes will be served by defining technology as the "state of the arts" as they exist at any one time, including both ideas and methods as well as applied inventions.