By Jeff Jacoby, Patriot Post - By bringing children into a world where things have gone wrong, parents improve the odds that there will be someone to help set things right. The number of human beings has nearly quadrupled over the past century, and mankind is flourishing as never before. People live longer, healthier, and more comfortable lives. They are better fed, better housed, and better clothed. Age-old evils — slavery, genocide, child mortality, illiteracy, world wars, deaths from natural disasters, and absolute poverty — have been dramatically curbed, if not yet vanquished altogether.