Clever Hans was all the rage in early twentieth-century Germany. Hans was a horse, and he was clever because he could do math, even quite complex computations. His owner could ask a question such as: “If Monday is the fifth day of the month, what day is the following Thursday?” Hans would stomp his foot eight times to give his answer.

This was not a scam. The owner truly believed in his horse’s mathematical prowess, and he toured Hans throughout Germany, but he never charged admission. Rather, he demonstrated Hans’s intellectual abilities for the purpose of advancing science.

A team of scientists and academic authorities studied Clever Hans and, finding no trickery, concluded that the horse’s talents were genuine. But then psychologist Oskar Pfungst set up a series of experiments and got some interesting results. First, Hans only knew the answer to the question if his owner knew the answer. And second, Hans only gave the correct answer if he could see his owner’s face. In the end, Pfungst concluded that the owner was unconsciously providing the horse with subtle body cues that let the horse know when to start and stop tapping its hoof. Hans was indeed clever, but more in the social than in the mathematical realm.

Around the turn of the twentieth century, there was a spate of such clever animal displays that were always debunked when experimental psychologists got a chance to study them. This led the noted comparative psychologist C. Lloyd Morgan to propose the following rule, now known as Morgan’s canon: Never explain a behavior in terms of a higher level of consciousness when it can be explained in terms of a lower level of consciousness.

This doesn’t mean non-human animals can’t be intelligent or perform intentional behaviors. It’s just that we don’t assume so until we have plenty of evidence. Since Clever Hans’s behavior can be explained in terms of the intuitive, largely unconscious reading of facial expressions, we don’t accept the idea that Hans was doing mental math, which requires considerable skill and focused consciousness. (Consider how you solved the problem we posed to Hans.)

Morgan’s canon is now the starting assumption in animal research. But it applies to human behavior as well. We go through our days mostly on autopilot, running routines and performing habits with barely a thought to what we’re doing. And there’s nothing wrong with that. Habits and routines free our minds for more important thinking.

Generally speaking, we’re only fully conscious in two situations. The first situation is when we’re performing a behavior that we haven’t done before or isn’t well practiced. Experienced drivers handle their cars with almost no intentional thought. But just think back to when you were learning to drive.

The other situation is when an unexpected event happens while you’re performing a well-practiced routine. You’re breezing down the freeway, merrily singing along to your favorite tunes on the radio, when suddenly the car on your left cuts into your lane. Instantly, your autopilot yields control to highly focused attention, and you’re so fully conscious of what’s going on that you get the feeling time has slowed down. You hit the brake. You swerve to the right. You glance in your mirror to make sure you steer clear of the car in the next lane.

Once we understand that we’re not fully conscious in every moment, we can get beyond the delusion that our behaviors are driven by intentional decisions. This bit of self-knowledge can take us a long way in improving our social interactions as well.

A pet peeve of mine involves drivers who sail through intersections just as the light is turning red. This is especially frustrating if I’m in the middle of the intersection preparing to turn left. Don’t you know how dangerous this is? What’s your hurry, anyway? Don’t you know you could cause an accident? It’s not only dangerous, it’s disrespectful to other drivers. So goes my train of thought.

The other day, I was driving along with the flow of traffic, engaged in a lively conversation with my wife. In other words, I was driving on autopilot, and my conscious attention was focused on her. I was keeping just enough distance behind a delivery truck, and I followed it through an intersection. That’s when I noticed the traffic light above me was red.

Yes, I know how dangerous that was. And I wasn’t in any hurry at all. Yes, I know I could have caused an accident. What I did was dangerous, and it was disrespectful to other drivers. I’m usually quite cautious about stopping on yellow (even when cars in other lanes zip on through). But this particular time, I just wasn’t paying enough attention.

I’m not saying this as an excuse for my dangerous driving. Rather, considering my own behavior makes me rethink how I evaluate other drivers. If I can run a red light unintentionally, why should I assume other drivers who run red lights are doing so on purpose? After all, Morgan’s canon tells us not to explain behavior in terms of a higher level of consciousness when it can be explained at a lower level. First blame the autopilot.

We gain peace of mind when we explain the behavior of others in light of Morgan’s canon. When I assume the driver running the red light or cutting me off in traffic did so intentionally, I feel angry. But when I assume the act was unintentional, my anger subsides, and I’m more ready to forgive.

Abiding by Morgan’s canon in our social life can reduce stress and frustration, freeing us to get on with more important things. When your spouse says something that hurts your feelings, when a coworker misses a deadline, when someone cuts in front of you in the checkout line, invoke Morgan’s canon, and assume the offense was unintentional.

This doesn’t mean you should let people walk all over you. You need to let your spouse know your feelings were hurt. You should tell your coworker you were inconvenienced. And you can point out that the line starts back there, not up here. But when you assume they didn’t do it on purpose, your tone of voice will be calmer, and they’ll be more likely to listen to what you have to say.

Horses don’t do math. And people aren’t out to ruin your day. Quite to the contrary, you ruin your day when take offense at other people’s thoughtless words and actions. Instead, if you can make a habit of thinking in terms of Morgan’s canon, you’ll enjoy more peace and happiness in your life.