Stephen Hawking, the brilliant physicist and author who died Wednesday at 76, was undeniably our age’s most well-known scientist. But he was also a great paradox.

I first met Hawking when he came to speak at Harvard in the mid-1980s. Not yet famous to the general public, he was nevertheless a celebrity within scientific circles. So it was no surprise to me that a standing-room-only crowd of faculty and students squeezed into the Science Center to hear what he had to say.

Hawking’s main claims to fame back then were crazy-sounding ideas about black holes and the origin of the universe. At the heart of both, he said, were “singularities” – mind-bending entities that are at once infinitely small and infinitely large. That, you could say, is the first paradox I will always associate with Hawking’s long, distinguished life and career.

Back then, the young maverick was also raising eyebrows by challenging the prevailing belief that nothing could ever escape from the mortal grip of a black hole’s irresistible gravitational field. He claimed that under certain circumstances, light of various wavelengths – what came to be called “Hawking radiation” – could indeed escape. That’s paradox No. 2.

Despite my disagreements with him, however, I am deeply, deeply saddened by his passing. The universe seems a bit quieter to me this morning because of his absence. And a bit darker, as if someone has snuffed out a bright supernova.

At that time, Hawking was already wheelchair-bound, having been diagnosed with amyotrophic lateral sclerosis (better known as Lou Gehrig’s disease) in his early 20s. Doctors predicted he would not live past 25. The fact that he survived to be three times that age is nothing short of a miracle. And what I consider paradox No. 3.

In the mid-eighties, Hawking was still able to speak, although barely. The Harvard presentation consisted of Hawking mumbling strings of sentences and then pausing for his assistant, standing alongside him, to translate. It was an arduous yet unforgettable experience.

Several years later, while I was still teaching at Harvard, ABC-TV hired me to be the science editor for “Good Morning America.” Around that same time, Hawking published “A Brief History of Time,” a book explaining, among other things, his novel ideas about the creation of the universe.

Sensing a good science and human-interest story, I dared to ask Hawking if he would let me interview him on his home turf in England. He was the Lucasian professor of Mathematics at Cambridge University – the same ultra-prestigious chair once occupied by the legendary Isaac Newton – and intensely private. He had never granted a network television interview – or any television interview, to my knowledge.

Fortunately for me, Hawking remembered our cordial encounter at Harvard and accepted. It also helped, I suspect, that I was a fellow physicist.

I needed to submit my questions well ahead of time, because by then Hawking was no longer able to even mumble. He relied on a synthesizer for speech, so he needed time to pre-record his answers to my questions.

When my crew and I arrived in Cambridge, we were astonished to find that Hawking, his wife Jane, and three kids all lived in a modest apartment in the basement of a student dormitory. That was also a paradox.

When the time came for cameras to roll, I asked my questions, then listened to the machine voice’s answers. Throughout the interview, Hawking remained slumped in his chair with a fixed smile on his mostly paralyzed face. To his day, it ranks as the strangest yet sweetest interview I’ve ever done – and I’ve done thousands over the years.

On our second day with Hawking, we set off to his office and classroom to film him teaching and to speak with his students. I’ll never forget Hawking’s mischievous smile as he tried outracing my camera crew across the sprawling campus in his wheelchair. He was a deep thinker, yes, but also a well-known prankster. Yet another paradox.

During our time with Hawking, things went so well he did something that shocked us: he gave me permission to interview his wife and kids – including his 9-year-old son, Timmy. During all of those interviews, Hawking sat nearby listening. At the end, when I went to say goodbye, he was teary-eyed. As was I.

In the years since those early encounters, I’ve taken Hawking to task on some of what I consider his zanier ideas. Most recently, I pushed back on his proclamation that the human species has less than a century to live and must colonize space in order to survive.

I’ve noted that for all of his brilliance and the public comparisons of him to Isaac Newton and other great scientists of the past, Hawking never won a Nobel Prize – nor did the scientists I know generally consider him in a league to earn one. Another paradox.

I’ve also pushed back on Hawking’s love-hate relationship with God and religion. Early on, he allowed for the possibility that God exists, but more recently he seemed hellbent on seeking ways for the universe to have created itself.

That, to me, will always be the grandest paradox of all – that Hawking could readily believe in such far-out ideas as imaginary time and a nothingness that is actually everything, but not the idea that God could possibly exist.

Despite my disagreements with him, however, I am deeply, deeply saddened by his passing. The universe seems a bit quieter to me this morning because of his absence. And a bit darker, as if someone has snuffed out a bright supernova.

There are many new, young stars ascending in science these days – some with ideas even more daring than Hawking’s ever were. But I doubt the world will see the likes of him again for a long, long time. He was that special.

Rest in peace, Stephen.