Why can everybody relax? Two reasons: contraception and abortion. And why do the guys at PRI ignore these reasons? Because they don't want to tell us that mortal sin is the reason we can relax. What would happen if every person in the world suddenly became a good Catholic? Let's run the numbers. Assume that a good Catholic family produces, on average, four children. Then the population doubles every generation. To make it easy, let's say a generation is thirty three and one-third years. Then we have three generations per century, and the population will increase by a factor of eight each century (2 x 2 x 2 = 8). Earth's population was 6 billion people in the year 2000; 3 billion were 24 years old and younger. Let's be conservative and consider those 3 billion to be the current fertile generation and ignore the rest of us. Since the population will increase eightfold each century, we will have 24 billion people by the year 2100, 192 billion by the year 2200, and 1.5 trillion by 2300. Maybe the earth can handle 1.5 trillion people, more than 200 times the number we have today, but I don't think I would want to be one of them. Think of America with not just one Detroit, but 200 of them. Not just one New York, but 200 of them. Not just one Southern California, but 200 of them. No thanks. By 2700, the earth would have 6.3 quadrillion people. Earth's land area is 1.6 quadrillion square feet. Yep, that's 4 people per square foot.