soul and its natural rights was readily assimilated by Christianity and has had a long and beneficent history in its influence on religion and social theory; but neither Plato nor Marcus Aurelius nor the high-minded Stoic lawyers ever started a campaign against the compulsory degradation of human beings in slavery because the institution was presupposed in the very structure of existing society. The victory for the extirpation of slavery came only when science through the harnessing of natural forces rendered recourse to slavery unnecessary.
A few illustrations of the way in which human muscles have been relieved may be given. The compressor machine enables one man to break up as much street pavement as eight can do with pick and shovel. The power corn-sheller enables one man to shell 720 bushels in the same time that eight bushels can be shelled by hand. A modern bakery turns out 2,000 loaves of bread an hour with a force of eleven men. A new automatic machine turns out 100 times as many table tumblers per man per hour as can be produced by hand. With a new spiral conveyor 18 man hours are now sufficient to unload a shipload of chemical fertilizer where 720 man hours were needed before. Machinery hitched to the photoelectric cell is relieving man of the exhausting monotony and tediousness in many jobs, and freeing him from many dangers. The miraculous electric eye sorts beans, lemons, peaches, raisins, cigars, checks and bills; it analyzes card records; detects missing labels; candles eggs; grades tiles, vegetables, tin plates; counts traffic, people, animals and so on; and it inspects numberless other things. No limit can be set to what may in the future be done by machines.
The load lifted from human backs by the introduction of power-driven machinery is strikingly illustrated by Professor Moulton who says that "the coal burned in the United States each day does more mechanical work than all the men in the country do in a year. Every person in the United States has 10 horsepower of mechanical slaves working for him—equivalent to 400 million slaves altogether. A ton of freight is carried a mile on railways at a total cost to the shipper which would buy the time of an unskilled laborer for only a minute or two. A 60-watt electric light is operated for almost an hour at a cost to the user of the federal tax on just one cigarette." Not many years ago the working day in most factories was 12 hours long for six days a week, or 72 hours for the week. This working period has fallen steadily to approximately 40 to 44 hours a week of 8 working hours a day. Only time and technical developments will tell how much shorter this is to become.
Thus science, by its conquest of force and space has enormously lifted life in its qualitative aspects. Men work less, produce more, consume more, and enjoy more education, goods, leisure and opportunities, especially in industrial countries where initiative has had most play and reward.
The conflict for intellectual freedom in which science has been involved since its emergence 300 years ago has been a conflict primarily of methods. It has not been a conflict between Truth and
