The human brain, especially one well-nourished by seafood, is endlessly inventive and the source of countless marvels.

It is also prone to error.

However intelligent or well-informed we are, we are susceptible to the most common bad mental habits. 

That’s why teachers are so important, beginning in grade school. But learning does not just transmit from old to young. If you have children or grandchildren, I suspect they are also good teachers, pointing out your mistakes in their squeaky voices, or driving you crazy by their bad examples of bad logic.  

We can be better thinkers if we catch ourselves making the most common mistakes at least some of the time. Here, according to psychologists, are a few to watch for:

We love stories—and trust them

Newspaper feature stories start with an anecdote because it makes the statistics and other abstract information in the following paragraphs more believable.

When we’re hard-headed, we know an anecdote is just one example, and should be less persuasive than solid statistics reflecting many examples.

But we’re impressed by details in one-time events (Oschatz, 2020). Ask any creative writing teacher! Details stick in our minds. Then we draw ridiculous conclusions from them. We think, “That brown-haired check-out lady at the supermarket, the one who got into a conversation and took twice as long as the blonde on the other side, made me late for my Zoom meeting. Brown-haired people are so slow! What is it with these brown-haired people?”

Try to laugh at yourself when you do this. You will do this over and over and, if you are patient and savvy, catch yourself more often.

We see cause-and-effect everywhere

Your husband, John, is missing—no one can find him.  You weep easily; it comes over you while you’re in public, while you’re driving. John loved Roy Orbison, the early rock singer. You put on a classic rock station in the car and you begin weeping. Then you hear Roy Orbison sing,

“Yes, now you're gone

And from this moment on

I'll be crying




Yeah, crying


Over you.”

Metal Newton's cradle
Sometimes, we can clearly see the cause and the effect. And sometimes, we want to see this sequence so badly…we invent it.

In the month after John’s disappearance, you hear Roy Orbison sing “Crying” on this station three times while you’re thinking about John. You feel that the two things must be connected. Your thoughts caused the song, perhaps because John is psychically reaching out to you. It is a deeply comforting thought.

It’s easy to see a connection that doesn’t exist. Remind yourself that all kinds of things are always happening at the same time. The online project Spurious Connections includes charts with seemingly synchronized lines that show, for example, the divorce rate in Maine from 2000 to 2009 seems to correlate precisely with per capita consumption of margarine (Vigen, 2021).

On the other hand, sometimes we don’t want to see a connection between two things and we ignore what is obvious to others. Emotions influence our logic.

We think we are better than we are

Aren’t you sure you’re morally superior to the people you don’t like? I confess it’s crossed my own mind. Psychologists call this the “self-enhancement effect.” As a rule, we tend to think we are more virtuous, have superior intelligence, and are more ambitious, friendly and modest than others.

Hello My Name Is sticker
We think we’re smart, especially about our chosen professions or passions. But humility is often more appropriate.

We exaggerate our knowledge as well, because it gives us social status. In one study, participants who rated their knowledge high in biology claimed to recognize the terms meta-toxins, biosexual, and retroplex. All were nonsense words made up for the test. People who considered themselves savvy about geography  were more likely than other people to say they had heard of the American cities Monroe, Montana; Lake Othello, Wisconsin; and Cashmere, Oregon, also imaginary. (Rosenzweig et al., 2015).

Maybe you’ve heard of the Dunning-Kruger effect, the idea that the least competent and knowledgeable are most likely to overestimate themselves. This is a convenient put-down, and it’s probably not true either (Jarry, 2020).

We think what we’re used to is “natural”

In fact, our ideas of what is “natural” are culture- and history-bound. Meanwhile, science, the effort to understand nature, keeps surprising us.

The great Greek philosopher, Aristotle, argued that some people were born to be slaves—“from the hour of their birth, some are marked out for subjection, others for rule.” Slavery was natural and therefore correct.

Centuries later, slaveholders in the United States argued that African Americans were biologically inferior to their masters, an argument that was taken seriously in the 1800s, even among scientists. That idea gave way to a “new natural”—a new idea of what is correct—the goal of freedom and respect for all.

Bottom line: Whenever you hear yourself saying “It’s only natural that…” keep in mind that change and growth are the most natural phenomena of all.



BBC. Ethics - slavery: Philosophers justifying slavery. BBC. Published 2014.

Jarry J. The dunning-kruger effect is probably not real. Office for Science and Society. Published December 17, 2020.

McKay R, Tappin B. The illusion of moral superiority. SAGE Journals. Published October 2016.

May C. Most people consider themselves to be morally superior. Scientific American. Published January 31, 2017.

Oschatz, C., & Marker, C. (2020) Long-term persuasive effects in narrative communication research: A meta-analysis. Journal of Communication, 70(4), 473–496. 

Rosenzweig E, Atir S, Dunning D. When knowledge knows No Bounds: Self-perceived Expertise Predicts claims of IMPOSSIBLE knowledge. SAGE Journals. Published July 14, 2015.

Sanford, J.B. Argument Against Women's Suffrage, 1911, against proposal in California.

Tom P. Why are people overconfident so Often? It's all about social status: Haas News: Berkeley haas. Haas News | Berkeley Haas. Published August 14, 2018.

Vigen T. 15 insane things that correlate with each other. Spurious Correlations. Accessed September 23, 2021.