# Math Geek Mom: A Puzzle from My Past

Learning what we once knew.

## By

April 30, 2015

When I teach the History of Math, I sometimes show the movie “A Beautiful Mind." Based on the life of John Nash, a mathematician who won the Prize in Economics in memory of Alfred Noble (often called the Nobel Prize in Economics), it tells the story of the man who invented game theory. I had to smile at a line in which the main character refers to Adam Smith as the “inventor of modern Economics”, since, in many ways, John Nash invented the approach that is what we now think of as truly modern economics; game theory. I found myself thinking of this recently when my daughter found herself hooked on a puzzle that I used to do when I was about her age; the Rubik’s Cube.

When I was much younger, I could take any Rubik’s Cube and restore it to its original state in a matter of seconds. Like game theory in Economics, solving the cube requires one to think several steps ahead; if I move this cube here, what will it do to the cubes on this side? And how does that change the cubes that are already in place. While relating to Economics, these questions are ones that also arise in our own lives. If I take this job, what will that say about my ability to follow another course in my career? In many ways, we are always solving multi-dimensional puzzles as we work to live the best life possible.

I made the mistake of telling my daughter that I used to be able to solve the Rubik’s Cube when I was younger. She therefore took only a few seconds to disrupt its original positions and handed me a cube with blue sides mixed in with white, red, orange, green and yellow sides. “Here, mom, fix this for me.” She asked. No problem, I thought.

Well, it seems that somewhere between my teen years and today, the part of my brain that knows how to solve the cube was disrupted. As much as I try, I cannot repeat the feat that I was very good at so many years ago. I had to admit to her that I could not remember how to solve the cube. “But give me some time, I am sure I will figure it out.” I told her.

I waited for her to leave to play with her friends, and snuck out my computer to pull up web sites claiming to teach one how to solve the cube. They all did a great job in teaching how to solve the first side, but from there, I was at a loss. The problem with a Rubik’s Cube is that solving anything beyond the first side disrupts what has already been solved. Indeed, the same can be said of life- making one decision costs one the opportunity to make other decisions. She came back home to catch me watching YouTube videos on how to solve the Rubik’s Cube and laughed. The next week, she told some friends that her mom, who has a Ph.D. and teaches math in a college, was watching videos about how to solve the cube that they fixed for her in seconds. Oh, well, I never said that I remembered how to solve the cube; just that I used to know how to solve it.

She now tells me that there are more advanced versions of the Rubik’s Cube, some that allow the cubes to rotate in more ways and some that are different shapes. She has yet to ask for one of these as a gift, but I suspect that such requests will come as more holidays arrive. Meanwhile, a friend has promised to teach her how to solve it, so she can soon teach me what I used to know. However, just in case her friend does not come through, does anyone know of a good reference that will really teach me how to solve this puzzle?

My heart goes out to the people of Nepal as they recover from the terrible earthquake of last week.

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