Killer Logic: The Unborn Genius

So my husband and I are childfree by choice. We don't dislike children, we just decided the whole parenting thing wasn't for us. Some people are completely horrified by this decision. After all, what kind of selfish jerk wouldn't want to have kids? Right. Anyway.

One particular argument always has me scratching my head.

"But...your child could be the one to cure cancer!"

Mmkay then. So basically, by withholding my DNA from the gene pool, I could potentially be depriving the world of that genius who finally unlocks the coveted cure for cancer.

Somewhere, in some relatively near future, a desk will remain empty, its chair unoccupied, for lack of the genius I would have produced.
A Nobel Prize will go unclaimed for want of the beautiful mind I would have begat. (Begatten? Begotten? Whatever)
And I guess I can understand the concern. The more kids we have, the higher the statistical odds that one of them will be Dr. AwesomeBrains.
But I'm admittedly a bit of a pessimist. That, and I tend to think in terms of what else I'm statistically likely to create. I mean, one of my kids could cure cancer, but what if their elder sibling winds up a serial killer?

When you think about it, the serial killer vs Nobel Prize winner vs cancer curer odds are not terribly promising. Take into consideration the number of each produced in the last century, and...well:
See??? In our efforts to bring forth the messiah of science, we could far too easily be unleashing a killer.
Even if my kid didn't end up on the FBI's Most Wanted list by third grade, let's face it: having a child because they could cure cancer creates an awful lot of pressure, and not just for the parents.
You gotta feel for a kid who only exists because enough people convinced Mom and Dad that their combined DNA could save the universe from cancer.

I mean, really. You are setting that kid up for one hell of an inferiority complex.
So if you're one of those people who approach me with that argument, and you wonder what's going through my head when I give you that eyebrow-up/head-cocked look...now you know.