Stephen William Hawking CH CBE FRS FRSA was born on January 8, 1942, exactly 300 years after the death of Galileo. He died Wednesday, on the anniversary of the birth of Einstein. He seemed fated to greatness. And if it seems appropriate to consider the course of his life in these grandiose, almost mythic terms, that’s because Hawking came to represent more than the sum of his jaw-dropping discoveries. After decades of struggling with (although “triumphing over” may be the more accurate term) an amyotrophic lateral sclerosis diagnosis that is normally fatal quite early on, Hawking was eventually confined to a wheelchair. A bout of pneumonia that required a tracheotomy left him unable to speak except through a computer. Of course, everyone knows this. These usually catastrophic debilitations seemed an essential part of who Hawking was, an important thread in his destiny. Issuing half-impish, half-Delphic pronouncements in the flat intonations of a speech-generating device, Hawking came to be the very embodiment of the triumph of the human mind over matter, the pure cogito of the ergo sum.

But was Stephen Hawking a celebrity? He was certainly a popularizer of science, appearing on television, talk shows, and even as an animated figure on The Simpsons. His 1988 book A Brief History of Time introduced multiple generations to the mind-bending wonders of black holes and went a ways in popularizing the field of cosmology more generally. For kids growing up in the 80s and 90s like myself, Hawking was as ubiquitous as Michael Jordan or Bono. This was intentional on Hawking’s part. As his colleague in the field Roger Penrose wrote, “Although the dissemination of science among a broader public was certainly one of Hawking’s aims in writing his book, he also had the serious purpose of making money. His financial needs were considerable, as his entourage of family, nurses, healthcare helpers and increasingly expensive equipment demanded.”

For very practical reasons, Hawking was forced to become popular. But that’s a feat easier said than done, especially in the theoretical sciences. It takes a unique spirit to balance the monomaniacal focus that pioneering work of any sort demands against the playful generosity of a popular communicator. And Hawking did just that.

To my mind, there are three traits in particular that allowed Hawking to create his public persona. Most importantly, he had a sense of humor. Just watch him messing with John Oliver. He was someone who genuinely enjoyed life, and his spirit was infectious. Secondly, he kept an open mind. Despite hovering halfway between atheism and agnosticism, he met with four popes and was a long-time member of the Pontifical Academy of Sciences. He was skeptical, but never obtuse or arrogant. And lastly, he thought in geometry. As Amanda Gefter explains in The Atlantic: “When Hawking set out to do his calculation, his disease had already made it impossible for him to write out long equations by hand, and he was forced to do it all in his head. That inspired him to think about things in a totally new way—to think not in numbers but in shapes. In geometry. He saw, in his mind’s eye, how event horizons affect the entire space-time they bind—he saw how they determine the symmetries of the whole space-time, which in turn determine what we mean by a vacuum and what we mean by a particle. He saw this grand, global picture, which changed everything, and he attributed it, in part, to his illness, which he once said was the best thing that ever happened to him.” Most non-scientists also think about the world in terms of shapes and geometry rather than equations. And so, in a strange way, Hawking’s disease forced his thoughts to take a form more recognizable to the common world, even if the ideas themselves were often knotty.

But Hawking was much more than simply a popularizer. He also performed the difficult mental labor of high-end theoretical cosmology. He recognized the second law of black hole dynamics, proving that the singularity, or point of infinite density, at the center of a black hole can’t shrink. He proved the existence of “Hawking Radiation,” which suggested that black holes could eventually dissipate over time. Using the concept of “imaginary time” he theorized that the universe may have no boundary. These and other concepts can’t be summarized in a sentence or two. In fact, it’s difficult to summarize them at all, but that became Hawking’s MO: doing the esoteric work, and then being able to get his neighbors excited about it. The fact that he was able to ascend to the mountaintop of advanced theoretical physics himself added a certain heft to his popularizations. He wasn’t just a spokesman. He was a messenger from a rarified plane of thought. Like Marco Polo, he wanted to tell you about the places he’d been. Of course, that place also happened to be the universe we all inhabit.

But was he a celebrity? In The Image: A Guide to Pseudo-events in America, Daniel Boorstin defined a celebrity as someone who is well-known for being well-known. That doesn’t fit Stephen Hawking. He was an explorer. He plumbed the physical architecture of the universe. He certainly didn’t belong alongside the Kardashians. Yet we as a public always seemed to want something more from him than a wonderfully communicable scientist of the highest order could deliver. To some, he was a poet. He made others question the fundamental building blocks of reality. Hawking himself wrote in A Brief History of Time, “Even if there is only one possible unified theory, it is just a set of rules and equations. What is it that breathes fire into the equations and makes a universe for them to describe?”

He was searching for the same thing in his own work that so many other non-scientists were. They were looking for what “breathes fire” into the science, the meaning of meaning itself, the metaphysical foundation that allows for existence. These, of course, are not answers that science could give Hawking or anyone else, no matter how elegant the description of the physical universe. Though, perhaps now, after a lifetime of exploration, he’s finally found what he’d been seeking.

Scott Beauchamp’s work has appeared in the Paris ReviewBookforum, and Public Discourse, among other places. His book Did You Kill Anyone? is forthcoming from Zero Books. He lives in Maine.