Donald Trump's Path-Independent Theory of Mind

How the U.S. president is like a Google ad test.

Playing to the audience.

Photographer: Chip Somodevilla/Getty Images

People have been discussing how Donald Trump interacts with other humans, guessing at the extent to which he is capable of anticipating or understanding how they think. Some believe he has no such “theory of mind.” I disagree: He has one, but it’s path-independent.

Remember when he thought people would like the fact that he’d fired FBI Director James Comey? Or the multiple times when he changed his story on why he did something? Those are the tell-tale signs.

Most people, when they try X as an explanation, won’t try “not X” afterwards, for the simple reason that they know their audience will know they were either lying before or they’re lying now. But Trump will try stuff until one of his attempts “works,” defined as eliciting approval. He’s path-independent, in the sense that he’s completely unconstrained by his previous words and actions. If neither “X” nor “not X” works, he’ll assume that it’s his audience that is being irrational.

In a prior column, I discussed the notion that Trump behaves like a machine learning algorithm. Well, his path-independent theory of mind fits perfectly into that metaphor.

When Google is trying some new shade of blue in the background of their ads, they will perform what’s called an “A/B test” to see what generates more clicks. If more people go for the ad with a lighter shade of blue, they will stick with it. What they won’t do, critically, is consider the possibility that their audience liked the light shade of blue only because it came after the darker shade. They will assume that the audiences are independent of each other, constantly refreshed and “new.”

The same approach might have worked well for Trump as a businessman. He probably would have encountered a wide range of scenarios: For every deal that went through, dozens might have failed. So trying X one day and Y the next would be like a real science experiment. Over time, he might develop pattern recognition, figuring out which tactic works best in certain kinds of situations. I assume that’s where he learned to put pressure on business partners for unreasonable terms and to demand oaths of loyalty from his employees.

Similarly, when Trump was campaigning, he actually did have a fresh audience on a daily basis. He could try out new things while re-using things that worked previously in similar situations, honing his craft with the direct and immediate feedback that he craves. His audience, in the context of a rally, was being refreshed constantly, just like Google’s ad customers.

I’d argue that Trump’s path independence operates on multiple levels. It’s evident at a meta-political level when he takes a stab at sweeping campaign promises that he never intends to fulfill. It’s also visible at the micro level, even within a given sentence: In his very strange recent interview with The Economist, for example, he kept attempting to adjust his message to obtain approval from his interviewers. He keeps things vague, and then pokes his way into a given explanation, but leaves himself room to change direction in case he senses disapproval.

It doesn’t always work for him. That said, he probably can’t act any other way. Consistency has no attraction for him, because he is fundamentally principle-free.

Trump’s problem now is that the audience isn’t refreshing. It’s all of us, nationwide and globally. We remember what he said and did yesterday. We notice when he changes his story, and we’re not amused. Meanwhile, he’s left truly confused as to why things aren’t working out in his favor.

This column does not necessarily reflect the opinion of the editorial board or Bloomberg LP and its owners.

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