Past Midway Ramblings on Business & Life

My Father Knew He was Fallible

For years, my father kept a slip of paper in his wallet, torn from a small 3 x 5 spiral notebook. On it, strangely, was a simple geometric sketch and a calculation of how far a 6-foot person could see before the horizon drops off due to the curvature of the earth. This is a curious thing to keep in one’s wallet.


My dad and my older brother (a teenager at the time) made this calculation while sitting around the kitchen table at my grandparents’ house. It was a teaching moment.1

Apparently, dad had calculated this before, as a young man, and had remembered the answer. But, much to his surprise, the answer this time was different from what he remembered calculating in his younger years.2

He double checked the math. Then, with a bewildered look, Dad said, “If you had asked me that question, I would have answered from memory with a high degree of confidence of being right.”

That is, he realized he had been wrong.

I later learned Dad had kept this scrap of paper in his wallet as a constant reminder that he could be wrong… that he was fallible. As we all are.

Side Note – Realizing We Are Wrong

It’s uncomfortable to realize we are wrong. But just prior to this realization, we were also wrong. We just didn’t know it yet.

There’s a significant difference between being wrong and realizing we are wrong.3 The difference isn’t in the circumstances, but in the awareness. The awareness creates the potential4 for change and growth.

Realizing we are wrong is the confounding recognition of our own ignorance and the prerequisite mental state to improve our thinking (requisite but not sufficient). Conversely, simply being wrong is often accompanied with the implicit assumption that we are right. Blissfully right. This is a dangerous place to reside. Not just ignorant, but delusional.

Ignorance is normal and may even keep us modest. If recognized, gaps between ignorance and knowledge are bridgeable. Delusional is clinical.

Extrapolating Lessons & Keeping Mementos

What I like about this story about my Dad…

  1. Dad created teaching opportunities through his intellectual curiosity.
  2. While teaching, he also learned. The lesson wasn’t about the correct answer to the problem, but about himself.
  3. This deeper lesson required a willingness to consider, and ultimately admit, his own fallibility, even in the face of certainty. This is intellectual honesty.
  4. From a single instance of faulty memory, dad extrapolated a broader framework of thinking. One that considers we might be wrong even in our most basic assumptions of what we “know” to be true. This is intellectual objectivity.
  5. Finally, he memorialized the lesson by keeping this piece of paper in his wallet. This indelible insight was clearly important to him.5

Teach >> Learn >> Contemplate >> Extrapolate >> Grow >> Remember.

Our Own Fallibility

My father was extremely objective and unusually rational in this thinking. He was way out on the long tail of the distribution of how people think in this respect. That is, he was very much in the minority.

For most of us, our steady-state assumption is that we are right most of the time. Our failure to recognize (much less admit) we might be wrong is seemingly pre-wired within us, written into our meta-code. The zero-energy state is apparently static thinking.6

It’s important to permit our views to be malleable. To continually iterate and improve our mental models as new data arrives is agile and adaptive. Recognizing we are fallible is the first step that enables us to consider revising our frameworks of thinking.

Or I might be wrong about all of this…

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  1. Dad was a thinker, extremely logical and enjoyed solving problems like this. He was also an excellent teacher who took time to help my brother and I learn how to think about solutions, not just solve them. This was apparently a learning exercise Dad did with my brother one day for fun. I was too young to follow the math at the time (which was often the case during these sessions… like the time we were at our kitchen table calculating the amount of rain, in gallons, that fell on our 72-acre pasture from the one inch of rainfall that we got that day. I was 6.)
  2. In case you are curious, a 6-foot person can see ~3.0 miles on the horizon (assuming a perfectly spherical surface of the earth).
  3. I feel compelled to give conceptual credit here to Kathryn Schulz and her insightful book Being Wrong: Adventures in the Margin of Error, which discuss these different states of wrongness.
  4. I say “potential” because it’s still optional.
  5. Wallets hold a limited number of items and yet this scrap of paper made the cut.
  6. It apparently requires lower levels of mental energy to defend our currently held beliefs with dogmatic demeanors than to re-map our world views.


  • I especially enjoyed footnote number 6… If thousands of people in our modern society were willing to accept mental challenges and remold their brain (as Paul said, take every thought captive…), we would be much less polarized culture. That’s my liberal arts take on an article about how your Dad contemplated this specific mathematical problem… Haha!

  • Your Dad was my roommate his freshman and my junior year of college. He was, in addition to one of the most intelligent, one of the most dedicated, humorous and honorable persons, even at that age, it is my privilege to have known to have known in my 77 years. By the way I was only the second best man at your parents’ wedding.

By Andy Jones
Past Midway Ramblings on Business & Life

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