WE'RE pretty familiar with the seed and the egg in our house. They've become like cartoon characters, like Road Runner and Coyote, chasing each other around the byways of biology. The seeds have tails (but not top hats) and swim. The eggs are round and go on a fantastic voyage once a month.
All this and more has been elicited over years of incremental kid information gathering, culminating one day in the Lincoln Tunnel, natch, in the question of how the seed and the egg wind up in the same place at the same time. Like Proust's madeleine, the look of horror and incredulity on my son's face took me back to the moment when I first heard the news.
Sex education in the '90s is complicated. Because my sons look upon my person the way I looked upon a transparent plastic model called The Visible Woman when I was a kid, they have asked many incisive questions about human reproduction, often in crowded trains while commuters strained for my explanation as though we were all in an E.F. Hutton ad. After their sister was born, they stared at her on the changing table as though they were at the drive-in and she was the screen.
Condoms, puberty, infertility: We've tackled the mechanics of them all. Sex education is good. So we are educating about sex.
But sometimes I feel as if I'm teaching geometry instead of something infinitely more intimate. I worry that in explaining sex technically, we fail to capture its essential humanity, even its sexiness. The parents of adolescents grimace at this. That last part, they say, the kids figure out for themselves.
Well, yes and no. I sat recently with a group of young women in their 20s and was struck by the difference between how they saw their sex lives and how my friends had seen theirs 15 years ago. The difference was fear. The younger women were looking for Mr. Right and Mr. Wrong at the same time.
In the age of AIDS, trust was an outmoded luxury and sex sounded much like Russian roulette. One woman had had a brief encounter with a fellow student and hadn't stopped worrying about it until she gave blood and passed the routine HIV screening. "I will never, ever, ever do that again," she said grimly.
These women did not invent the nexus of sex and fear. I've heard about it from women older than I am, women whose contraception consisted of the mantra "Oh, God, don't let me get pregnant." I've heard about the sexual encounters that led to marriage to a relative stranger.
Somewhere between now and then were those of us who grew up after the pill but before AIDS was a household acronym. The time was called the sexual revolution, which overstated the case. But in retrospect it does seem revolutionary, this freedom from fear, this freedom to make a mistake and not pay for it with your life, one way or the other. Sometimes I feel as if we grew up between two times of sexual peril, like someone too young to be drafted into one war and too old for the next.
We learned about ourselves through trial and error, and there was plenty of the latter. It made some people crazy, this freedom: Retributive sex has always been a popular prejudice, from homes for wayward girls to AIDS as a spurious validation for homophobia.
It's why some of our mothers talked about sex as a pitfall, not a pleasure. And our kids talk about pitfalls, too, the one they know from public service messages and Magic Johnson and a favorite uncle, who got thinner and thinner and at last disappeared. Their burgeoning new world of sexuality already has fear edging the horizon.
The other night my son was watching a documentary called "The Miracle of Life," which follows the seed and the egg up close and personal. (Up very close -- the Fallopian tubes get pretty scary.) He was cheering the seed on, as though conception were a cross between the Super Bowl and Super Mario Brothers, and then he said triumphantly, "That's how I started out."
I was glad that he saw himself as part of the process; perhaps that is what I fear gets lost in all the logistics. We all know there's a lot more to this than 28-day cycles and the vas deferens. There's biology, it's true, but there's also psychology, humanity, morality. The seed and the egg. Sex and death. And love, of course. Nobody said this was going to be easy.
Anna Quindlen is a columnist for the New York Times.