Think of a trait that brings people together.  It could be jokiness, religiosity, libertarianism, love of books, or fascination with role-playing games – or seriousness, impiety, statism, hatred of books, or contempt for role-playing games.  Take your pick. 

Now suppose that the parent-child correlation on the trait you picked is exactly zero.  Then no matter what you’re like, you should expect your kids to be at the 50th percentile.  If you’re normal, that’s a pretty good deal; at least on average, your kids will be just like you.  But the weirder you are, the less your kids will typically resemble you.  Even if you’re at the 95th, 99th or 99.99th percentile, you can expect your kids to be perfectly average.  In a world of zero parent-child correlation, weird people have little in common with their children.

In the real world, of course, parent-child correlations almost always exceed zero, and are often substantial.  This doesn’t boost the similarity between normal people and their children; no matter what the parent-child correlation is, parents at the 50th percentile typically have children at the 50th percentile.  But a positive parent-child correlation does boost the similarity between weirdos and their children – and the weirder you are, the bigger the boost.  Take a look:
 

 

Parent-Child Correlation

 

 

r= 0

r=.5

 

You

Stranger

Child

Stranger

Child

Percentile/

Expected

Percentile

50th

50th

50th

50th

50th

95th

50th

50th

50th

80th

99.99th

50th

50th

50th

95th

Notice that regardless of the value of r, normal people can expect to be like their kids.  But that’s not saying much, because normal people can expect to be like any random person they meet!  The story’s very different for weirdos.  By definition, weirdos never have much in common with random strangers.  With a zero parent-child correlation, weirdos will feel equally alienated from their children.  As the parent-child correlation rises, however, weirdos’ incompatibility with strangers stays the same, but their expected compatibility with their children gets stronger and stronger.

Now let’s look at these facts like a mad economist.  There are two ways to surround yourself with people like you.  One is to meet them; the other is to make them.  If you’re average, meeting people like yourself is easy; people like you are everywhere.  If you’re weird, though, meeting people like yourself is hard; people like you are few and far between.  But fortunately, as the parent-child correlation rises, weirdos’ odds of making people like themselves get better and better.  This is especially true if the parent-child correlation largely reflects nature rather than nurture, because you won’t have to ride your kids to emulate you; they’ll do it on their own initiative.

You might object that meeting like-minded friends is always easier than making like-minded children, no matter how high the parent-child correlation gets.  If you’re only looking for casual relationships, that’s probably true.  But if you’re looking for deep, time-intensive, life-long connection, blood really is thicker than water.

The lesson: As your weirdness increases, so does your incentive to have kids.  If you like football and American Idol, you’re never really alone.  You don’t need to build a Xanadu for yourself.  But if you’re a lonely misfit, oddball, freak, or weirdo, then find a like-minded spouse and make new life together.  Let the normals laugh at you.  You’ll have each other.

P.S. I’m speaking at Western Carolina University on Friday at 2:30 in the Forsyth Auditorium.  If you’re there, please introduce yourself. 🙂