If you enjoy reading with your children, wonderful. But if you skip the nightly book, you’re not stunting their intelligence, ruining their chances for college or dooming them to a dead-end job. The same goes for the other dilemmas that weigh on parents’ consciences. Watching television, playing sports, eating vegetables, living in the right neighborhood: Your choices have little effect on your kids’ development, so it’s OK to relax. In fact, relaxing is better for the whole family. Riding your kids “for their own good” rarely pays off, and it may hurt how your children feel about you.

Once parents stop overcharging themselves for every child, the next logical step is straight out of Econ 101: Buy more. When you raise your children the easy way, another child is more likely to pass the cost-benefit test. This doesn’t mean you should copy the Duggars with their 19 children; when prices fall, Econ 101 says “Buy more,” not “Buy dozens.” But whatever your priorities, the science of nature and nurture tilts the scales in favor of fertility.

As you weigh your options, don’t forget that the costs of kids are front-loaded, and the benefits are back-loaded. Babies are a lot of work even if you’re easy on yourself. But the older kids get, the more independent they become; eventually, you’ll want them to find time for you. So when weighing whether to have another child, you shouldn’t base your decision on how you feel after a few days — or months — of sleepless nights with a new baby. Focus on the big picture, consider the ideal number of children to have when you’re 30, 40, 60 and 80, and strike a happy medium. Remember: The more kids you have, the more grandkids you can expect. As an old saying goes, “If I had known grandchildren were this much fun I would have had them first.”

Bryan Caplan, “The Breeders’ Cup: Social science may suggest that kids drain their parents’ happiness, but there’s evidence that good parenting is less work and more fun than people think”, The Wall Street Journal, 2010-06-19