Since the days when the cosmic energy of coal was first harnessed to the looms of England, mechanical contrivances of almost miraculous ingenuity have followed one another in such rapid succession that men have come to place undue reliance upon machinery for the solution of the difficult human problems that impede progress toward the good life and a worthy civilization. Just as the earlier generations failed in the spiritual preparedness necessary to the conversion of the technical triumphs of Newcomen and Watt, Fulton and Stephenson, and a host of others to the higher ends of civilization, so our generation shows a similar disposition to rely upon the wonder workers of mechanical science to save us from the disastrous consequences of muddling along in the field of human relations whether in industry, in the nation, or among the nations. But the good life is not to be won by mechanical invention alone. One of the outstanding lessons of the World War was that great inventions in the realm of the physical and chemical sciences may be destructive of the very civilization which it is their higher mission to serve. Unless we have the spiritual capacity to make the technique of science obedient to the commandment to love our neighbor as ourselves, superpower systems, high-voltage transmission, the internal-combustion engine, may again intensify the exploitation of man by man, the clash of groups for power, the brutality of international wars for possession. We men and women of the twentieth century have developed a complacent habit of priding ourselves upon our scientific open-mindedness, our respect for facts, our eagerness to accept the revelations of authentic scientific investigation and experiment. As we mount into the clouds on the wings of the aeroplane or catch the voice of the radio operator out of ethereal space, we have a tremendous sense of intellectual emancipation, a thrill of escape from ancient bigotries and superstitions. There is some warrant for this self-congratulatory attitude in so far as it relates to the physical sciences. We have reason to be proud that we have banished the primitive fears that led an earlier age to persecute men like Galileo for telling the truth with respect to the place of the earth in the stellar universe. We are sufficiently emancipated to know that the inventors of the dynamo, the turbine engine, the spectroscope, wireless telegraphy, and high-voltage electrical transmission are not guilty of heresy. When Steinmetz forges a thunderbolt and sends it crashing across his laboratory, we do not burn him for witchcraft. The inquirers into the nature of the atom, the structure of the cerebral ganglia, or the chemical composition of the nebulae in the Milky Way are free from medieval taboos.