In Memory of the Great Teachers I Have Met in My Life (IV)

By Li Lei April 13, 2026, in Itaca, NY

This is directly translated from the Chinese version of Blog (https://mp.weixin.qq.com/s/_N62P_8Cbh2fsgiIp1Dyjw)!

Epigraph

A teacher’s guidance is like the spring breeze; a teacher’s grace runs as deep as the sea.

Han Yu once wrote in On Teachers: “A teacher is one who transmits the Way, imparts knowledge, and resolves doubts.” When I first encountered that line, I understood it only in the most formal sense. It seemed to belong to classrooms, lectures, books, examinations. Only later, with time and distance, did I begin to understand how much larger the word teacher really is.

In life, the rarest gift is not simply to meet someone who teaches you facts or skills, but to meet those who quietly shape the deeper architecture of your mind. They steady you when you are still uncertain. They lend you their vision before you have fully formed your own. They may not always speak in maxims, and they may not even look, at first glance, like the solemn figures we imagine teachers to be. But years later, when you turn around and look back, you realize that much of what now feels most deeply yours—your habits of thought, your sense of proportion, your way of seeing the world—was gently marked by their presence.

I have been thinking of the mentors who left such marks on my life. They taught me far more than what could be contained in a syllabus or a degree. They enlarged my world, sharpened my mind, and, in quiet ways, helped form my character.

This essay is about the last of those great teachers in my life, and the one who shaped my professional path most profoundly: my postdoctoral advisor, Peter Morrell.

If I had to name the person who truly taught me how to do scholarship—how to think, how to build an intellectual life with rigor and soul—it would probably be Peter.

It was eleven years ago, in the fall. There was already a touch of coolness in the air. At the time, I was looking for a postdoctoral position in a lab that worked more directly on crops and on questions with a stronger applied dimension. By chance, I heard from a friend of mine that Peter might be recruiting a postdoc, though no one seemed sure whether the position was still open. I looked through his lab website, liked what I saw, and decided to write to him, thinking it was worth trying.

He replied almost immediately and soon arranged an interview.

I still remember that interview with unusual clarity. It remains in my mind like a stretch of autumn light—clear, unhurried, quietly bright.

I had expected the usual format: a formal presentation, a polished summary of my previous work, a series of serious questions. But Peter did not interview me that way at all. Instead, he simply talked with me. We began by discussing major figures in evolutionary biology—Masatoshi Nei, Chung-I Wu, Wen-Hsiung Li—and from there wandered into the intellectual lineages behind them, the ways ideas move across generations and shape a field over time. Later he told me about his own projects, the questions he was thinking about, and even, almost casually, what life in the Twin Cities might be like if I moved there.

Before the conversation ended, he only suggested that I speak with some of the students in the lab, so I could get a feel for the department, the resources, and the atmosphere.

A week later, he sent me an offer. Not long after that, he helped me begin the process of applying for a work visa.

I remember being struck by how direct and efficient he was. There was no performative formality, no dragging things out, no unnecessary complication. His style felt like the season itself—clean, brisk, and unexpectedly generous.

When I finally arrived at the lab, I found myself thinking something embarrassingly unacademic: he was very handsome.

Not in a flashy way, but with an ease and brightness that gave him, to my eyes, something of the aura of an old movie star. At the same time, the lab itself was surprisingly modest. Because most of the work was computational, there was not much equipment, and whenever wet-lab work entered the picture, everything felt a little makeshift. Peter, too, did not fit my old idea of what a mentor should be. He sometimes arrived a few minutes late to meetings. Occasionally he brought his dog—or even his baby—into the lab. In the middle of a scientific discussion, he might suddenly drift into a story about everyday life, then drift back again as if the shift required no explanation at all.

At first, I did not quite know what to make of him.

The mentors I had known before him had all been serious, formal, and controlled—people who wore the role of “advisor” with unmistakable authority. Peter was different. He was relaxed, informal, quick to joke, and unconcerned with appearing impressive in the conventional way. He overturned my expectations almost immediately. Yet there was also something unmistakably old-fashioned about him, in the best sense. If he saw someone wearing ripped jeans to play basketball, he would sincerely wonder whether the person was struggling financially, and might genuinely consider offering money to buy them food.

At the time, I did not yet understand that someone could look so loose on the surface and yet be so deeply grounded underneath. He never performed authority, but he possessed it. He never seemed rigid, but he always had measure. He was like a tree in the wind: the branches moved freely, but the roots were deep.

As I got to know him better, I came to see that Peter’s greatest influence on me did not lie in any single lesson. It lay in the way he changed my understanding of scholarship itself.

The first thing he taught me was how a real project begins.

In his view, research was never supposed to start with “let’s gather a mountain of data and see what we can make of it.” He had little patience for work that relied on accumulating material first and finding a story afterward, or for papers built on descriptive analysis alone, without a real question at their center. He had a particular disdain for shallow projects that could be published simply because they were data-rich, even if they lacked conceptual depth.

For him, scholarship began elsewhere. It began with reading deeply. With learning the landscape of the literature until you could see where the field had already gone, where there was already light, and where something remained obscure. Only then could you ask a question worth asking. Only then could you build a defensible hypothesis. And only then could you design analyses and experiments in a way that allowed evidence to gather naturally around that question.

That way of working reshaped me.

What made his style especially distinctive was that he rarely asked us to give the standard kind of oral presentation about our projects in lab meeting. Instead, when a project was just beginning, he often had us start by drafting the outline of the eventual paper. Not after the results were in. Not after the data had accumulated. At the very start.

What is this paper actually trying to answer?
What is the central thread?
How should the story unfold?
What literature is missing?
What analyses need to be done?
What role should each figure play?

The outline came first. The storyboard came first. Everything else—the analyses, the experiments, the figures—grew from that underlying structure.

That was when I first understood, in a deep way, that good research is not only about generating results. It is about shaping form. It is about building an internal logic strong enough to hold everything together. Research is not a pile of materials; it is an organism. It must grow according to a pattern.

At first, I worried that because we did not give many formal presentations in the lab, my speaking skills might weaken. Later I realized Peter was training us in something more demanding than performance.

He created a small course designed for people outside bioinformatics, and instead of teaching it entirely himself, he had the members of the lab take turns. We were responsible for preparing lectures, designing handouts, creating assignments, and explaining difficult bioinformatics concepts to people from very different backgrounds. The course became so well known that even people from another campus began attending. Often, dozens of people would show up.

Looking back, I now see how brilliant that was.

It is one thing to present your own work to people already fluent in your field. It is another thing entirely to take something complex, abstract, and intimidating, and make it understandable to those who do not already speak the language. That kind of teaching forces you to do more than talk well. It forces you to understand.

Peter was, in this way, teaching us not merely how to present, but how to communicate. Not merely how to appear knowledgeable, but how to make knowledge available to others. There is a difference, and he understood it.

His weekly lab meetings shaped me just as deeply.

They were not project updates. They were paper discussions. And he had one strict rule: no slides.

At first, I found this baffling. In my previous academic environments, a lab meeting almost automatically meant PowerPoint—figures, summaries, clean takeaways, a carefully managed structure. But Peter insisted on stripping all of that away. You brought the paper. You read it. You explained it. You argued with it.

It took me time to understand why.

Without slides, there was nothing to hide behind. No design polish, no visual scaffolding, no way to rely on style instead of substance. You had to read carefully. You had to think carefully. And because nothing mediated your attention, the discussion went more directly to the paper itself.

The range of papers he chose was astonishingly broad. We read foundational classics from the early decades of the field, first papers by major thinkers, brand-new bioRxiv preprints, beautifully written papers, badly written papers, high-level research articles, and papers about gender bias, diversity, and undergraduate education.

At first glance, this might have looked eclectic. In reality, it was a method.

He was training our taste.

After each paper, he would ask us: What works here? What is genuinely original? What is elegant? What is weak? What could have been done better? Over time, this cultivated something invaluable: the ability to read without submission. Not to be overawed by famous names. Not to confuse prestige with quality. To admire real brilliance where it existed, but also to question it when necessary. To see that even imperfect papers can contain sparks of insight, and even celebrated work can have blind spots.

This habit of reading critically—and reading with taste—has stayed with me ever since.

But those discussions shaped more than my scientific judgment. They also sharpened my sensitivity to the broader ethical and social atmosphere of academia. Through them, I became more alert to the ways bias—gendered, racial, institutional—moves through academic life. I began to understand that scholarship is not only about findings and methods. It is also about the climate in which people are trained, heard, dismissed, encouraged, or ignored.

There is another thing about Peter that left a lasting impression on me: he cared deeply about reputation.

I do not mean reputation in the shallow sense—not status, not applause, not ambition for prestige. I mean something older, almost classical. Something closer to the Chinese ideal of the scholar who guards his name because he guards the integrity behind it. Peter had that quality. He treated his writing as an extension of his moral seriousness.

He was extraordinarily demanding of his own papers. Manuscripts that already seemed, to anyone else, quite strong could suddenly be torn down and rebuilt from the beginning. He would rethink the structure, revise the logic, sharpen the language, and begin again if necessary. Even after a paper had been accepted, he might continue polishing it—revising, smoothing, refining—until it felt fully worthy of his name.

He approached reviewers’ comments with the same seriousness. No matter how minor or sharp the criticism, he responded with care and sincerity. He answered each point thoughtfully, trying to understand what the reviewer was really asking, and how the paper might actually become better because of it. There was nothing performative in this. It was not strategy. It was character.

That affected me deeply.

He taught me that scholarship is not simply the production of results. It is also the outward expression of a person’s standards. The way someone handles their own writing says something about how they handle their own conscience. Real rigor is not about impressing other people. It comes from refusing to be careless with one’s own name.

Peter also brought me back to reading.

I had always admired the breadth of his knowledge, but over time I realized that it did not come only from professional expertise. He was simply a true reader. He read science, of course, but also history, mathematics for non-specialists, social thought, and all kinds of books that had nothing immediate to do with work.

Under his influence, I slowly recovered a reading life I had lost. Reading stopped being merely instrumental—something done to solve a problem or complete a task—and became again what it had once been for me: a private source of nourishment and delight.

There is a special kind of relief in opening a book at night that has nothing to do with productivity. It is like opening a window in a life that has grown too narrow. Air enters. Space returns. The mind remembers it was not made to live by utility alone.

What looks irrelevant to scholarship often sustains it most deeply. A mind cannot become spacious if it lives only inside the limits of a profession.

Peter also influenced me in many smaller, subtler ways.

He taught me things about networking, about storytelling, about how to express ideas with both clarity and appeal. More importantly, he had a rare gift for recognizing what was singular in other people.

He seemed genuinely delighted by the fact that I could almost recite the academic lineages of major scholars from memory. He would often ask me, unexpectedly, “What’s this person’s background?” He also appreciated my eye for figures and data visualization, and often encouraged others in the lab to show me their figures and ask what I thought.

To be seen like that by a mentor matters more than simple praise. It is a form of recognition that gives shape to your emerging self. It tells you that what others might overlook in you may in fact be part of your gift.

To be seen that way while you are still young is no small fortune. Many people live for decades without ever fully learning where their own particular light resides.

There is an old Chinese saying: “One day as teacher, a lifetime as father.” Though I left Peter’s lab more than ten years ago, we have remained in touch.

Even now, we still exchange messages from time to time. If he comes across a paper he finds interesting, he may invite me into the discussion. When he writes a review, he sometimes sends it to me first and asks what I think. And later, when I ran into confusion in my own academic life—or into people and situations so absurd they could only be described with a weary laugh—he was still someone I could turn to.

That continuity reminds me of something I once heard about his own academic lineage: even accomplished scholars, long after becoming senior figures themselves, still return to their mentors for guidance. That, to me, is one of the truest signs of a real teacher-student bond. It does not end with graduation. It does not dissolve when a contract ends or a move is made. It changes form, but it remains.

It is like a river that remembers its source even after it reaches the sea. Like a tree whose branches have long spread outward, but whose roots remain sunk deep in the same earth.

Some people teach you for a season. Others become part of the internal conversation of your life.

There is one final thing about Peter that I have always admired: his openness to the new.

From the early days of Sanger sequencing and writing software in Java, to Perl, Python, and now AI, he has always remained willing to learn, adapt, and engage with what is emerging. This has never struck me as trend-chasing. It comes from something deeper—a scholar’s refusal to let knowledge harden into habit.

Some people grow older and gradually become closed rooms, sealed against new air. Others become more open with time, not less. Peter belongs to the latter kind.

He taught me that the best scholars are not those who remain permanently perched atop what they already know, but those who keep the courage to walk toward what they do not yet understand. Scholarship is not a territory one arrives at once and for all. It is a life of repeated departures.

Looking back now, I feel more and more strongly that what Peter gave me was never just a set of research practices or a handful of useful professional lessons.

He gave me a frame for scholarship.
A standard for intellectual honesty.
A way of carrying seriousness without stiffness, rigor without cruelty, openness without loss of depth.

He taught me that scholarship can be exacting without becoming sterile. That thought can be sharp without becoming harsh. That one can hold very high standards and still remain warm, humorous, and deeply human.

Perhaps that is what a great teacher really gives us—not only knowledge, but a fuller way of being.

When I think of Peter now, what comes to mind is not one dramatic moment, but an accumulation of light. A conversation. A comment on a draft. A way of reading. A way of revising. A habit of asking better questions. A standard quietly held.

Human encounters are mysterious that way. Some people pass through our lives and disappear into the crowd. Others remain, like a fine spring rain that seemed almost silent when it fell, but whose work becomes visible later, when all the grass has grown.

I offer this essay in gratitude to my mentor, Peter Morrell—
for his teaching, his example, and for all that continues, even now, to cast light across the years.