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Interview with Ralph Hertwig

Behavioural Science is a rapidly expanding field and everyday new research is being developed in academia, tested and implemented by practitioners in financial organisation, development agencies, government ‘nudge’ units and more. This interview is part of a series interviewing prominent people in the field. And in today's interview the answers are provided by Ralph Hertwig.

Ralph began his scientific career in 1995 at the Max Planck Institute for Psychological Research in Munich. In 1997 he moved to the Max Planck Institute in Berlin. In 2005 he was appointed Professor of Cognitive Science and Decision Psychology at the University of Basel, before becoming the director of the Max Planck Institute for Human Development since 2012 and heads the Center for Adaptive Rationality. He has published in top ranking journals, his work focusing on why a limitation also constitutes a strength: so how and why adaptive heuristics can be as effective as complex optimisation models.


Who or what got you into Behavioural Science?

For the record, I consider myself a behavioural/cognitive psychologist rather than a behavioural economist. But how I got into the field was through studying at the University of Konstanz, where Gerd Gigerenzer was a professor at the time. I was fascinated by his work and by Kahneman and Tversky’s work on how people make decisions, and how good or bad those decisions are.

I was really struck by the conceptual tensions between the positions and the profound questions about the human mind and rationality they implied—and that’s basically what drew me to the field.

But I think my main concern, my main motivation was always a practical one: How can we help people make better decisions?

What is the accomplishment you are proudest of as a behavioural scientist?

I tend to be most excited and, by extension, perhaps proudest of the things I’ve worked on most recently, so there’s a strong recency effect in any feelings of pride.

But more generally I’m proud of work where I feel I’m stepping outside of my intellectual box. That is most likely to happen when I work with people across different disciplines, and I’m not a captive of my own knowledge and thinking.

If you weren’t a behavioural scientist, what would you be doing?

I’m a bit of a political news junkie—at least my wife thinks so. It’s true that I’m very interested in the world and its historical trajectories, in the sense of where we’ve come from and where we’re going.

So if I weren’t a psychologist, I think I’d be interested in a combination of historical science, political science, and philosophy.

How do you apply behavioural science in your personal life?

I’m just writing a paper on what we call self-nudging, which is the idea that someone who is let into the secrets of nudging can also apply those tricks and insights to their own life.

In my personal life, for example, I think carefully about where to place tempting bars of chocolate or desserts. And with respect to digital tools I use, I think carefully about the settings and defaults I choose. So I’m more cognizant of the choice architecture around me—whether it be in the food environment, the digital environment, or elsewhere—and try to empower myself to change that choice architecture in a way that I think works in my favour.

With all your experience, what skills would you say are needed to be a behavioural scientist? Are there any recommendations you would make?

I think the major skill is openness, by which I mean both openness to ideas across disciplines and openness to people.

On the one hand, I think we should try to benefit as much as possible from what other fields are working on and thinking. On the other hand, it’s my impression that new ideas tend to come from interactions with others. So I’d recommend the cultivation of intellectual and social openness.

How do you think behavioural science will develop (in the next 10 years)? That reminds me of a quote that’s often attributed to Niels Bohr, “Prediction is hard, especially when it’s about the future.”

It’s hard to predict the future of a field. But I hope three things will happen: First, that we’ll see a plurality of good theories that are rigorously tested—in particular, good theories of bounded rationality, where I mean good in terms of high psychological realism.

Second, that those theories will give serious consideration to the impact of the environment (and not just cognition) on human behaviour.

Third, I hope that the current interest in behavioural science evidence for public policy making will prove not to be a fad, but will be sustained far into the future. I believe that behavioural science evidence will be needed to address many of the great problems of our time—including climate change, polarization, obesity, and misinformation, to name just a few.

Which other behavioural scientist would you love to read an interview by?

I think Herbert Simon would have had some wonderful insights. I’d also love to read an interview with Ulrike Malmendier (University of California, Berkeley).


Thank you so much for these amazing answers Ralph! I will make sure to reach out to Ulrike, afraid that Herbert might be a bit beyond my abilities to contact.

As I said before, this interview is part of a larger series which can also be found here on the blog. Make sure you don't miss any of those, nor any of the upcoming interviews! Keep your eye on Money on the Mind!


Behavioural Science

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