Secretary of State Rex Tillerson and President Trump take questions from reporters at Trump National Golf Club in Bedminster, N.J., in August. (Pablo Martinez Monsivais/AP)

Forgive me for dredging up ancient history, but back on Oct. 10 — an eternity in Trump time — Forbes magazine published an interview with the president in which he challenged Secretary of State Rex Tillerson to an IQ contest. Veteran Trump-watchers rushed to their e-files to show that this is a recurring theme. Trump brags about his IQ as freely as he boasts about his interior decorating; it's like he has a chandelier between his ears.

If only I had a time machine to summon my 12-year-old self. That gormy little nerd would definitely throw down with the president.

In 1973, a much brighter version of me spent several hours in the school library untangling tricky word problems and picturing irregular solids turning in space. It's a miracle I got any of the answers right, given that 98 percent of my mental energy was consumed by the breathtaking transformation the previous summer had wrought on the girls in seventh grade, and most of the remaining 2 percent was storing memorized dialogue from "Gilligan's Island."

The lad's results, however, were impressive enough that — for a few weeks anyway — school officials eyed me with the mixed shock and pride of Farmer Arable gazing on Wilbur the pig under a spiderweb spelling out "radiant." Thus began a lifetime's discovery of the pointlessness of IQ tests and whatever it is that they measure.

I'm not saying that intelligence is useless. When I drive across a bridge or board an airplane, I give thanks for engineers who are a heck of a lot better than I am at math. As for genius, of course it exists. How else to explain a Michelangelo, a Curie, an Ellington or a Turing? The rare spark is struck in some unmapped dimension.

Yet to apply a single label, be it intelligence or genius, to the multifaceted power of the human brain, and then to reduce the label to a number, is folly. Brainpower shows in so many ways, from critic Helen Vendler reading a poem to quarterback Tom Brady reading a defense; from architect David Adjaye building a museum to author J.K. Rowling building a universe to investor Warren Buffett building a portfolio. Harvard University's Howard Gardner is clearly correct when he observes that humans possess multiple intelligences in varying degrees. Mine may be more linguistic, yours more spatial, another person's more musical or interpersonal or mathematical.

Compared with my 12-year-old self, I've undoubtedly lost at least 10 or 20 percent of my IQ points. What I've gained over the decades is a deep appreciation for all the things I don't know, and will never know, because they require varieties of intelligence in which I am lacking. And thank God, because my world is so much richer for it. Albert Einstein is often credited with saying "the more I learn, the more I realize I don't know."

Amen to that.

Trump's notion that intelligence is reflected in a single number — wearable on a jersey, flashable on a scoreboard — is the opposite of wisdom. Worse, it is the root of an intellectual isolation that endangers the country he leads. Trump finds himself increasingly at odds with his own staff and at war with would-be allies. He is squandering perhaps the most precious presidential power: the ability to surround oneself with a challenging mix of insightful and experienced advisers.

Some highly intelligent women and men serve on Trump's staff, Tillerson among them. Yet sources tell Vanity Fair that the president has been fuming lately, "I hate everyone in the White House." Frustrated with Congress, he attacks the political intelligence of Mitch McConnell, the moral intelligence of John McCain, the diplomatic intelligence of Bob Corker. A smarter president would be hungry for dissenting views and willing to hear from well-meaning critics, because listening is learning, and the more you learn, the more you win.

Oliver Wendell Holmes Jr. suggested that intelligence matters less in a president than the qualities of judgment, discipline and discernment that he called "temperament." That is even more true in our world of increasingly specialized knowledge and rapid change. No person, no matter how bright, can begin to know more than a small corner of all that a modern presidency encompasses.

I guess we'll never find out how the young DVD would fare in an IQ showdown with Mensa Don. But I know one guy who could kick Trump's tail for sure. His name was Socrates, and he lived in Athens nearly 2,500 years ago. Though the IQ test lay far in the future, Socrates spent a lot of time thinking about these matters — in a vivid demonstration of what Gardner calls "intrapersonal" intelligence, or the ability to understand oneself.

Here's what Socrates concluded: "How is not this the most reprehensible ignorance, to think that one knows what one does not know?" If Trump is so smart, let's hear his answer to that.

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