Ideology takes a back seat in modern politics, and that’s not a good thing.

People identifying themselves as “conservative” or “progressive” are associating themselves less with a school of thought than with the avatars representing those terms in our national political war.

I’m talking about the cults of personality around people like Bernie Sanders and Donald Trump.

Call someone “ideological” today and it’s a pejorative. We aren’t supposed to care about the philosophical underpinnings of public policy. Modern politics is about an endless campaign to defeat and embarrass the other team.

I suppose I’m a bit old fashioned in thinking we should still care about why we support certain candidates, and certain political movements, and certain types of policy.

Can you imagine a political debate which revolved around ideas, and not a competition to see who can be the most outraged?

Recently I had a moment which reinforced why I favor conservatism and small, limited government.

I am the father of a 3-year-old boy who has an August birthday. So imagine my trepidation when I came across a New York Times column written by Harvard researchers who found a strong statistical link between children with August birthdays and Attention Deficit Hyperactivity Disorder (ADHD).

“In a study published in The New England Journal of Medicine, we found that among several hundred thousand children who were born between 2007 and 2009 and followed until 2016, rates of ADHD diagnosis and treatment were 34 percent higher among children born in August than among children born in September in states with a Sept. 1 school entry-age cutoff,” the authors of the column wrote. “No such difference was found among children in states with different cutoff dates. The effects were largest among boys.”

Children born shortly before the cutoff date for school enrollment will be the youngest members of their class. Which means they’ll be months behind most of their classmates in terms of development and maturity.

Months, at young ages, matter a great deal.

This leads teachers, observing a child in the context of their peers, to see ADHD where a more reasonable explanation is age. “Indeed, some evidence suggests that teachers and other school personnel are more likely than physicians or parents to first suggest that a child may have A.D.H.D,” the Harvard researchers tell us.

Passionate, professional educators are making deeply consequential mistakes in evaluating the behavior of children for no reason other than the arbitrary age cut offs which dictate school enrollment.

What does this have to do with ideology and conservatism?

It shows the world is complicated. Public policy is a blunt instrument. Favoring aggressive, interventionist government policies seems like hubris to me when the side effects can be so unpredictable that something as banal as an enrollment cutoff date can cause a spike in diagnoses of ADHD.

We know far less about the world than we like to think, and that ought to urge us toward caution when using the power of government.