In August of 1950, when I was just a little tyke and my sister Laura but a babe in arms, our family set out in our 1947 Kaiser from Princeton, New Jersey, for parts West. We were moving out to California so that my dad could take up a new position in physics at the almost-unknown institution named Leland Stanford Jr. University. En route, we passed through many states and innumerable gas stations. I loved the smell of gasoline when we filled up, and was fascinated by the logos of the many different brands of gas. One day, as we were passing through Ohio, my dad pointed at the sign of the Standard Oil of Ohio station where we had stopped:

The SOHIO logo that my dad showed me could be read upside-down.

He offhandedly commented that if you twisted your head around, you could read it upside down. He even said it out loud: “Oy-hose.” What a silly-sounding, meaningless word! I practically split my sides. “OIHOS” was the funniest thing my 5-year-old self had ever heard. It was also the first ambigram I had ever seen.

This essay is an adapted excerpt from Hofstadter’s new book.

Well, actually, it wasn’t a true ambigram, but it was a close cousin to one. Let me explain. By ambigram, I mean a piece of writing expressly designed to squeeze in more than one reading. The etymology combines Latin’s ambi, meaning “two-sided,” with Greek’s gram, meaning “piece of writing”—and thus, if you look at an ambigram one way, it says one thing, and if you look at it another way, it says another thing (or possibly the same thing)—and deliberately so. A true ambigram is intentionally designed so as to have that Janus-like property. Since it’s unlikely that the creator of the SOHIO logo had the nonword OIHOS in mind as a rotated reading, I hesitate to call it a true ambigram, although, as my dad keenly observed, it had two pronounceable readings.

When you engage in “ambigrammia” (the act or art of producing an ambigram), you are not so much creating something new as discovering something old—or rather, something timeless, something that already (sort of) existed, something that could have been found by someone else, at least in principle. Ambigrammia is thus neither fish nor fowl, in that it floats somewhere between creation and discovery.

Let me spell this out a bit. Some ambigrams, when you see them, make you think, Oh, that was such an obvious find. A triviality! Anybody would have seen that possibility a mile away. Those are discovery-type ambigrams.