Wow, I was thinking that the strongest natural instinct is to survive. To survive we get an education or learn a trade. Between getting ready to go to work, then work, then coming home from work, having energy for sex was just a fringe benefit.

Teaching children that sex is just another thing to express your love for your spouse would be the proper Christian thing to do. Oh no, I said "Christian" I hope I am not in trouble. Ok. Take the Christian equation out and teach the children that it would be pragmatic to concentrate on sex when you find your soul mate?