"A baby is God's opinion that life should go on. A book that ..." — Carl Sandburg quote meaning

A baby is God's opinion that life should go on. A book that does nothing to you is dead. A baby, whether it does anything to you, represents life. If a bad fire should break out in this house and I had my choice of saving the library or the babies, I would save what is alive. Never will a time come when the most marvelous recent invention is as marvelous as a newborn baby. The finest of our precision watches, the most super-colossal of our supercargo plants, don't compare with a newborn baby in the number and ingenuity of coils and springs, in the flow and change of chemical solutions, in timing devices and interrelated parts that are irreplaceable. A baby is very modern. Yet it is also the oldest of the ancients. A baby doesn't know he is a hoary and venerable antique — but he is. Before man learned how to make an alphabet, how to make a wheel, how to make a fire, he knew how to make a baby — with the great help of woman, and his God and Maker.