Commencement speaker to Ph.D. grads: You are part of a proud tradition of doubters

Clint Chapple, Distinguished professor in the College of Agriculture’s Department of Biochemistry, made these remarks during Purdue’s summer commencement on Aug. 6.

WEST LAFAYETTE, Ind. — I have the honor of speaking to almost 300 newly minted Ph.D. graduates on what is likely to be one of, if not the, biggest days of their lives so far. I have taught for almost 30 years, and I’ve given well over a hundred scientific lectures, but today I'm supposed to sound smart, maybe a little bit wise and not too boring. That’s a daunting challenge for a biochemist! So I felt that I should come up with some sort of theme for this address. Something around which to structure the wisdom that I’m supposed to exhibit today.

But let me first say congratulations. You’ve done amazing, unique and impactful work and are about to be recognized with the Ph.D. You have worked hard for many years in your quest for this degree. I know it was hard, but I hope that at least, at times, you were able to enjoy the ride. 

I also want to acknowledge that you have been the research engine of this university. I hope that you realize what you have contributed to Purdue, to your colleagues and to your faculty advisors. And to the many of you who have been graduate lecturers, teaching assistants or lab mentors, you should know that you’ve also had a big impact on the undergraduate students of Purdue.

So back to my theme. Two months ago, Provost Akridge was kind enough to meet with me to discuss this address. He’s a pretty smart guy, so I thought I might get some tips from him. I learned then that he was the speaker who addressed Purdue’s first Ph.D.-only graduation ceremony only a few years ago! He told me that the graduation he addressed was the first after the COVID lockdown, so he chose as his theme “hope.” Well, I thought that was an interesting response, because I had been considering “doubt” as the theme for my speech. Those apparently opposing themes might well reveal personality differences between me and the provost, but maybe I can explain why your tendency to think of doubt as something negative is, for the most part, not what I’m attempting to draw out today.

There is one thing that I hope each of you has learned during the last few years. In fact, I think this is probably the most important thing that there is to learn during your Ph.D. And that is to doubt how much you know. 

That statement may or may not surprise you. And many of you have family members here today, and I wouldn’t blame them if there were surprised by what I’m saying. They probably feel that you are among the smartest and most accomplished people they know. Here you are graduating with your Ph.D., and yet I’m asking you to focus on what you don’t know, rather than your achievements over the past five or six years?

So why is doubting your knowledge important? Because as all of you must know by now, research is hard. It’s easy to make mistakes. Technical mistakes are fairly easy to deal with. You can often see when you’ve done something wrong. But the errors of interpretation, those are the tricky ones. Have you thought of all possible explanations? Are you fully aware of foundational work done by others before you? Have you rigorously tested your hypothesis? Doubt is inherent to hypothesis testing. If you seek to prove your hypothesis, your confirmation bias will almost certainly lead you to do so. You all know that, instead, we try to disprove hypotheses.

So doubt your data. Do an additional experiment or analysis or survey, or whatever you do in your own field, but do it another way or with another technique, not to validate your previous results, but to determine whether or not they are leading you to the correct conclusion. Reviewer #2 isn’t always wrong. 

Doubt your interpretation. Solicit the input of others who may look at your problem and your data in another way or who have a different set of skills or life experiences. They may help you see things a different way, and maybe not just your results, but the very question you are asking.

Doubt the literature. People have been wrong before. The beauty of research is that it is not dogmatic. We abandon ideas that no longer fit the data and are then compelled to develop new theories to explain our world and our place in it.

I suspect that many of you are familiar with doubt in other ways as well. Completing the Ph.D. is a long and taxing endeavor, and some of you may have doubted that you would finish and be here today, but here you are, so again, congratulations.

Some of you may even still doubt that you deserve the Ph.D. or are nervous about the expectations that accompany it. How many of you have heard the term “imposter syndrome”? Wikipedia defines it as when “an individual doubts their skills, talents or accomplishments and has a persistent internalized fear of being exposed as a fraud.” How many of you have it? I still do. So thinking back to when I was where you are today, I’d like to read you a quote that I put as the front piece of my Ph.D. thesis. I have always taken it to be about imposter syndrome. It is from the novel “Cat’s Eye” by Canadian author Margaret Atwood. It goes like this.

“Apart from all this, I do of course have a real life. I sometimes have trouble believing in it, because it doesn’t seem like the kind of life I could ever get away with or deserve. This goes along with another belief of mine: that everyone else my age is an adult, whereas I am merely in disguise.” 

I think a little bit of imposter syndrome is good. It keeps you humble. But be careful about it. Doubting yourself too much can be a liability. It’s just another example of how everything is best in the right measure.  And remember, we don’t give Ph.D.’s to just anybody. You’ve earned it.

So you might argue that I’m being somewhat hyperbolic, and to some extent I am. After all, you are all now experts in your field and know a great deal. But perhaps upon realizing how much you have learned in the course of your studies, it would be good to reflect upon how much those seated around you have also learned. How each of them are scholars in their own right. So when it comes to holding opinions on topics outside of your area of scholarship, it is good to remember that there is someone out there for whom that topic is their area of scholarship. That understanding is an excellent foundation for respect for others.

My time at Purdue has given me plenty of opportunity to learn this lesson. For many years now, I have been involved in faculty promotions and served on university award committees. I can tell you that it has been humbling to learn firsthand about the expertise at this university and to gain an appreciation for the achievements of the faculty. And again, I don’t mind pointing out that their successes were made possible by the efforts of graduate students like you all sitting here today.

There is another aspect of doubt that we should all find very troubling and that will be a great challenge to your generation. And that is the doubt in expert opinions that has been placed in the mind of the public. Never before in my lifetime have we seen such an assault on facts and the deliberate seeding of misinformation to sway public opinion, often in the hope of political or financial gain.

Hundreds of thousands or more people died from COVID-19 because the advice of the CDC to wear masks to slow the transmission of the virus was called into question. Every day, our climate is worsening because the expert and unanimous advice of the hundreds of climate scientists who make up the Intergovernmental Panel on Climate Change is not taken seriously enough or even ignored. Sadly, this is the world that you are inheriting. I hope you take this situation as a clarion call. Each of you should be proud of the academic tradition through which you’ve been trained and consider it a license to speak out forcefully for informed and well-reasoned approaches to social and governmental decision-making.

But on the brighter side, going forward, I want to challenge you to doubt what we know and to doubt the limits of what we can do and be. I think this applies no matter what path you take once you leave this university.

We used to think that the sun revolved around the earth and that the earth is flat. Of course, some people still think the earth is flat, but that’s a topic for another day. We used to think that a human would die if they went faster than the speed of a galloping horse. We used to believe that organisms could come into existence through spontaneous generation. We have pushed past those mental boundaries because people dared to doubt that those assumptions were correct.

You are part of that proud tradition of doubters. You have succeeded because, as the saying goes, you stood on the shoulders of giants. Well, thanks to what you have accomplished here and will accomplish in the future, others will soon be standing on your shoulders. So pay it forward. Mentor someone, or as many people as will listen to what you have to say. If you don't, your legacy is your own work. If you do, you can enjoy the reward of witnessing the success of others and know that your impact is greater than it would have been otherwise.

You’ve taken the first step. You’ve educated yourself and learned how to educate others. Some of you have learned that science can enable us to understand the world around us. Some of you have learned that languages and the arts are essential to human lives and have the power to calm the soul or call it to action when necessary. Some of you have become engineers who understand how to take new knowledge and apply it in ways that can benefit the human population and the world around us. Whatever your training, you can and will have an impact. It’s a big responsibility, but today you are earning your Ph.D.

You can do it. No doubt about it.