“Don’t let the bastards wear you down.”

That phrase, instilled in Dr. Anthony Fauci when he was a student at the Jesuit-run Regis High School in New York City, might as well be the motto of his professional life.

Even though he chose a career centered in science, medicine and public health, controversy has always had a way of finding him. By being willing to examine his own positions, he often found a way to turn a brewing storm into something constructive.

Fauci chronicles many such moments in his new memoir, “On Call: A Doctor’s Journey in Public Service.”

Fauci had already been in the public eye as the longtime director of the National Institute of Allergy and Infectious Diseases at the National Institute of Health, but he became a veritable household name at the start of the Covid-19 pandemic as part of the White House Coronavirus Task Force, which was charged with monitoring and mitigating the spread of the virus.

Fauci spoke frequently to the worried and bewildered American public at government news conferences, giving status updates and offering guidance on such topics as face masks, social distancing, school closures, hospitalization rates and, eventually, vaccines. Many credit him with helping the country navigate the uncharted waters of the coronavirus crisis with his medical expertise, calm demeanor and signature Brooklyn-tinged gravelly voice.

At the same time, Fauci was navigating his own political headwinds – some from his boss, former President Donald Trump, who tried to play down the threat of SARS-CoV-2 even as he initiated Operation Warp Speed, the $10 billion-plus public-private partnership focused on rapidly developing vaccines as well as therapeutics.

Plus, many coronavirus deniers, conspiracy theorists and antivaxxers blamed Fauci personally for struggles with school closures, mask mandates and vaccine recommendations. Even now, Fauci recently testified, he still faces death threats.

The pandemic was not the first time Fauci found himself in the center of a political and medical maelstrom. He was in the hot seat during the HIV/AIDS crisis of the 1980s, when his agency spearheaded the effort to fight the widening epidemic. HIV/AIDS activists called him and the entire medical establishment out for not doing enough or moving quickly enough to help people infected with the virus.

Yet throughout his career, Fauci seems to have taken public criticism in stride and used it, even, to build something better. It was an attitude he learned in childhood.

“The Jesuit priests, when you thought that all of a sudden the whole world was pounding on you, they would say ‘Illegitimi non carborundum,’ which means ‘don’t let the bastards wear you down,’ which … lately, that is a very relevant and appropriate saying,” Fauci told CNN Chief Medical Correspondent Dr. Sanjay Gupta.

“They don’t get me down to the point of interfering with what my work is, but it does wear and tear on you,” he added.

Fauci recently sat down for a conversation with Gupta — one of the many they have shared over the years — to discuss his life’s work and his legacy. These excerpts have been edited lightly for length and clarity. (Listen to more of the conversation on the podcast “Chasing Life with Dr. Sanjay Gupta” here.)

Dr. Sanjay Gupta: I want to talk about the 54 years of public service — almost 40 years, as you say, as director of the National Institute of Allergy and Infectious Diseases. Go back to June 5, 1981. That was a date you really talked a lot about in the book. What’s the significance of that?

Dr. Anthony Fauci: I was in my office in the clinical center at the NIH, and I read the June 5 [issue of the CDC’s Morbidity and Mortality Weekly Report, which described five cases of Pneumocystis carinii pneumonia among five gay men in LA] and I looked at it and I said, “Gosh, what a curiosity.” This is strange that they’re all gay men — but maybe there was talk about using poppers or drugs to enhance your sexual experience that maybe somehow had the collateral effect of suppressing their immune system.

But it bothered me. Boy, you really have got to suppress the immune system a lot to get pneumocystis [a serious lung infection caused by a common fungus]. … So I put it aside, saying “it’s probably a fluke, and it’s just going to disappear.”

The real transforming thing came one month later, in July of 1981, when the second MMWR came; this time, 26 — curiously — all young, otherwise healthy gay men, not only from L.A. but from San Francisco and New York City, who presented not only with pneumocystis but with Kaposi’s sarcoma and multiple other opportunistic infections.

I can say — retrospectively, when you try to evaluate the different landmarks in your life, in your career — reading that MMWR totally transformed my professional career because I made the decision right there, even though I had a very successful career up to that point … I said, “this is a brand new disease.  And even though I don’t know what it is, there’s no doubt it’s an infection. … And it seems to be destroying the immune system.” And here I am: boards in internal medicine, boards in infectious diseases, boards in clinical immunology. I said, “If there’s one disease that I have to study, is this disease.”

Gupta: I don’t think many people who sort of know you from Covid realize that in many ways, you went through some of these same challenges before with HIV/AIDS. Not just new disease, trying to find new therapeutics, but the activists. What was that part of your life like?

Fauci: Well, naturally, people ask about the difference or similarity between the pushing back against me and the government in HIV and pushing back against the government and me as the face of Covid. … It is as different as peanuts and watermelons.

It just is very different because the [HIV/AIDS] activists were trying to get the attention of the authorities, the scientific authorities and the regulatory authorities, that the time-proven way of approaching the development of interventions for a new disease doesn’t work well for a disease that’s rapidly killing themselves and their friends and their loved ones.

So they wanted a seat at the table. … So their confrontation to us was based on a good thing. I think back to John Lewis’ “good trouble” versus bad trouble. They made good trouble for us because they wanted us to just put ourselves in their shoes. …

Again, one of the best things I did in my career was to, instead of running away from them the way most of the scientific community did … I said to myself, “This can’t work, so let me put aside the theatrics and the disruption and listen to what they have to say.”

And what they had to say made absolutely perfect sense to me. And I said to myself, “If I were in their shoes, I would be doing exactly what they’re doing.” That’s when I invited them in to sit down with us and said “let’s start talking.” … It became such that they became an important part of the community scientific effort to address HIV with therapeutics, with prevention, with regulation, to the point now where they’re on all of our advisory committees. They’re part of the discussion. And quite frankly, many of them turned out to be some of my closest friends.

Gupta: But just to punctuate this point, though, at that time, going back 40 years, did you feel that way, the way you’re describing it now? I mean, this idea that, “Hey, look, there might be something to be gained from these confrontations”?

Fauci: The thing that drove me was empathy, which has been something that has driven my motivation about medicine and about anything that I’ve done, that goes back to my family, that I describe in the book: my parents and my training in the Jesuit schools. There’s empathy for people who are in trouble and people who are suffering.

When you combine empathy with listening to them — just forget the screaming and the yelling. Just listen to what they’re saying. And I’ve got to tell you, it just made perfect sense to me. So my interaction and my response to them, as I often get asked, is dramatically different than someone, on the basis of no evidence, accuses you of killing people or that scene of Marjorie Taylor Greene at the hearing. I mean, come on. That is nothing like what the [HIV] activists were doing.

Gupta: What do you want your legacy to be? How do you want people to reflect on Dr. Anthony Fauci?

Fauci: I’ve thought about that, and when I think about legacies — I really, honestly mean this — I will leave that to other people to decide. I know what I’ve done … with the development of drugs for HIV, with the development of the vaccine for Covid. I know that, but that’s not [for me to] say, “I want my legacy to be this,” because people are going to have different interpretations of that …

But what I would want my legacy to be, something that I am certain of, is that I have given it 100% every single day. And in the sports analogy, I can say I always left it on the field or left it on the court … I never held back. I just gave everything I could for the discipline I’m in, which is science, medicine and public health. That’s what I’d like my legacy to be.

Listen to the full “Chasing Life” episode here. And join us next week on the podcast when we examine the link between exercise and happiness.