My mother made me wear sunscreen a lot when I was younger. She got me into the habit from the age of 12. Daily sunscreen. It's kind of a pain to remember to smear lotion all over your face every morning. But, now that I see that it's delaying my aging process, I'm glad I've taken the trouble. It never occurred to me to whine to my mother that she had no right to tell me what to do with my skin, since she didn't wear sunscreen every day when she was young. I figured she must have learned something from the fact that she didn't.
Some parents have to teach much more difficult lessons from the wisdom of their experience. Parents who behaved stupidly in their teens are often worried about how to tell their kids not to do the same. "What if they ask me if I ever drank/did drugs/slept around? I'll look like a hypocrite! They'll never listen to me again!" In this case, experience serves to discredit the person giving advice. This is also often used as a criticism against people who make mistakes and then encourage others not to repeat them. Dawn Eden, for instance, after leaving a life of promiscuity is encouraging chastity. Hypocrite! people say. You can't tell us not to do that when you used to do it yourself!
This is a strange twisting of what a "hypocrite" is. A hypocrite deliberately leads people to believe that she is righteous, while at the same time not behaving in a way consistent with the image she projects. (Think of the Pharisees in the Bible, who put great effort into appearing holy, but whom Jesus rebuked for not being holy in their hearts.) If Dawn Eden were a hypocrite, she would still be leading her old promiscuous life while on her book tour. People who has learned from past experience, acted upon it to become better and live differently, and who provide the wisdom of past experience to others are, by definition, not hypocrites, and should keep a pocket dictionary handy to educate those who accuse them of being otherwise.
Then on the other hand we have the occasional person who has fortunately avoided one stupid decision or another. If a person who leads a chaste life encourages others to do the same, she will be ridiculed with the opposite. "How would you know promiscuous sex is wrong? You have no right to judge! You've never tried it!" People who prefer not to listen to the teachings of the Church on marriage and sexuality often write off the advice of priests on the same grounds. "How can someone who isn't married give me advice on marriage?" Or, one that pro-lifers sometimes hear, "How dare you tell me not to have an abortion. You don't know what it is like to be pregnant and unmarried/impoverished/still in school. Go away and let me make my own decision."
Is it not possible that those who lack experience with certain things may themselves have already learned from the experiences of others? Priests, for example, may not be married, but they are the ones in the confessional who hear about when people cheat on their spouses. They counsel engaged couples, and married couples, and parents. They hear about all of these problems from many, many people who experience them. Patterns are bound to emerge at some point. They learn from the experiences of others, and pass it along. A person who encourages chastity, or natural family planning instead of artificial birth control, or avoidance of drugs and excessive drinking may be doing so because of their positive experiences with the things they advocate.
Basically, no matter what one's background, it is impossible to comment on certain moral issues without getting accused of hypocrisy or ignorance by somebody. Both kinds of reactions have this in common: they deny that it is possible, or even useful, to learn from any experience except one's own. Both reactions imply that people cannot relate to each other unless their lives are exactly alike.
Let us return to the issue of sunburn, rather than sex. Suppose a person went to the beach every day from age 14 to age 30, sat in the sun and tanned and burned her self to a crisp. Suppose she found herself with wrinkles and melanoma. Suppose she wrote a book about experiences of the downsides of excessive beach side sun exposure (wrinkles, age spots, skin cancer, etc.) and offered strategies to avoid them. Suppose our response was, "That's just your experience. My skin isn't the same exact shade as yours, so you can't judge my risks! I'm going to lay out on the beach and go to the tanning booth as much as I want and you can't stop me! Butt out and keep your agenda off my skin!"
The folks who sell Botox would just love the extra business.
The trouble is, we're more afraid of wrinkles and melanoma than we are of STD's or even more invisible spiritual and emotional damage that can come from immoral behavior. People go to a lot of trouble to take preventative measures against aging, but they are not generally as careful when it comes to things like sex, alcohol, and drugs.
I know it's fun to live in the moment, but a hint of forethought here and there when it comes to what we allow in, on, and otherwise in contact with our bodies would be useful. It's ok to be careful about the important stuff. As a certain movie character once said, "You see how picky I am about my shoes, and they only go on my feet!"
Just a thought.