What does it take to become a researcher?
The Making of a Researcher is a new mini-series exploring the paths scientists take to reach where they are today, highlighting their growth from beginners to experts.
Through interviews with faculty members in various fields, we’ll explore the necessary steps to becoming a researcher and how Princeton professors play a part in that process.
In this first feature, Professor Casey Lew-Williams, Chair of the Psychology Department and Director of the Princeton Baby Lab, reflects on his journey in developmental psychology and his role as a mentor to aspiring students in the field.
When Professor Casey Lew-Williams first arrived at the University of California, Berkeley, where he did his undergraduate studies, he had no idea that research would become his life’s work.
“I didn’t even know that developmental psychology existed or that research was this really big backbone of how a university works,” he said with a laugh.
It was foreign to him at the time that “there were all these research labs and scholars in every building devoting a majority of their time to scholarship.”
His first glimpse into child development came from working at a childcare center near his dormitory, followed by a summer at an emergency shelter for foster children.
Even though he had already considered psychology as a major, his wake-up call came from reflecting on the kinds of places and activities that drew him in. He found that “apparently there’s an academic field devoted to studying learning, development, and growth,” and through this reflection, his path toward developmental psychology began to coalesce.
Working in labs gave Professor Lew-Williams a new sense of belonging—“a home away from home full of people with common interests,” as he described it. Sharing insights, meeting regularly to talk about papers, and discussing research designs became a refuge from massive lecture halls where personal connections were harder to find.
What stood out to Professor Lew-Williams and solidified his passion for studying developmental psychology was how the field deviated from the mainstream.
“When I go to talks in psychology, they’re often with adult participants studying memory or perception. That’s interesting, but my mind often goes to, ‘Well, we’re looking at an end state here. How did the system come to be?’ There’s a big mystery there. Developmental psychology gives us a chance to understand how these systems form and evolve.”
Now, as a faculty member in developmental psychology, Professor Lew-Williams describes the field as trying to address “a really hard puzzle.”
The brain and behaviors are complex on their own; studying them together with another layer of environmental factors makes understanding how children grow and learn much more challenging. More importantly, a touch of creativity is always present in the field, as researchers spend most of their time working around and with the fact that “the people they’re studying can’t tell them what’s on their minds.”
“You almost never see the same study design twice,” Professor Lew-Williams said. “Sometimes your participants can’t even speak, so you have to develop creative ways of figuring out what you want to know.”
When asked about his current priorities as a scientist, however, Professor Lew-Williams said, “I consider myself a mentor first and a scientist second.”
“That’s my rank order. It’s not everyone’s, and that’s okay, or at least they’re tied for first.”
For him, mentorship isn’t just a part of science; it is science.
“Mentorship and advising of emerging scientists is what science is all about. It’s about developing ideas, scaffolding for others, being present in a lab so you can learn from others and help them learn.” His philosophy of mentorship centers on fostering curiosity while helping students discover what matters most to them.
That process often begins with legitimizing students’ own interests. “A great process is hearing what students’ real interests are and meeting them halfway within what I can advise effectively,” he said. Encouraging students to take ownership of their curiosity, rather than simply following preset paths, leads to what he calls “really good science and creative science.”
“If I only assigned ideas from my own head, our lab wouldn’t be nearly as creative,” he added. “It’s those links across people that allow for novel ideas to emerge. We do everything from small tweaks on prior research to projects that are very novel and effortful because they’re new ways of thinking. Everything in between is welcome in science.”
The same philosophy of mentorship drives how he structures his lab. Students start with foundational, hands-on work that helps them learn the rhythm of research. Within a semester or two, students begin taking on more specialized roles: coding behaviors from videos, working alongside graduate students or postdocs, and developing consistency and reliability in their observations. By the time they reach junior or senior year, many design independent projects that reflect both their own interests and the lab’s broader questions.
“Fast-forward from the beginning of junior year to the end of senior year, a tremendous amount of growth happens,” he said. Students learn to design studies, collect and analyze data, and interpret results within a theoretical framework. “From generating a feasible design to writing a senior thesis, you go from low-level decision making dozens of times to abstract theoretical thinking about what it all means. That combination of low-level and high-level thinking is what science is.”
For him, mentorship threads through every stage of that process, “even in small doses.”
When asked to distill what it truly means to become a researcher, Professor Lew-Williams paused before answering: “It’s a process of having the maturity to recognize in yourself what you’re genuinely interested in and curious about. That can happen when you’re trying or not trying. Listening to yourself, catching yourself in the moment when you’re thinking about something you’re genuinely interested in. It is hard. Taking the next step to act on it is hard too. But students who have the maturity to come to terms with their genuine interests and apply that to their scientific pursuits are more likely to succeed.”
That reflection, pairing curiosity with self-awareness, captures the essence of his message. Becoming a researcher isn’t about chasing results; it’s about learning to listen to your own curiosity, to think deeply, and to grow because of and with your interests.
— Angel Toasakul, Natural Sciences Correspondent
