Julien Lie-Panis

Why do societies rely on rigid moral rules? Don't lie. Keep your promises. Don't steal. We all recognize there are good reasons to make exceptions. So why are moral rules so often categorical? Our new paper proposes an answer. 🧵

Had an amazing time with Dave & David!

Join us. www.tse-fr.eu/iast-researc...

This week's Cooperation Colloquium: Nikoleta Glynatsi @nikoletaglyn.bsky.social Revisiting Axelrod: What makes a strategy successful? Date: Oct 30 Time: 14:00 UTC+1 (Vienna) / 9am NYC Note the earlier starting time if you are in Europe. Sign up: list.ku.dk/postorius/li...

The 2027 European Human Behaviour & Evolution Association Conference is coming to Zurich Mar 30 - Apr 2! 🇨🇭 Abstract submission opens Nov 1, registration Jan 8. Please share and follow us to stay up to date with all things #EHBEA2027 www.ehbea2027.com @ehbea.bsky.social @uzh-ch.bsky.social

Consider joining us in Zurich for EHBEA 2027! This is a cool interdisciplinary conference bringing together anthropologists, psychologists, economists, and behavioral biologists. We've got excellent plenary speakers! Follow @ehbea2027.bsky.social for all the updates! See www.ehbea2027.com for detail

This week, we talk to @oliviermorin.bsky.social about the psychology of cultural evolution. youtu.be/minH1eiJrLM?... epthepod.podbean.com/e/olivier-mo... podcasts.apple.com/us/podcast/e...

New preprint! Computational Humanities needs falsifiable theories. With 25 Paris-based researchers who share the same ambitions for the field and had an exciting conversation. zenodo.org/records/2349...

Opportunity: Penn MindCORE Fellowship! MindCORE seeks postdoctoral researchers for our Research Fellowship. Housed in Arts & Sciences at Penn, MindCORE is an interdisciplinary effort to understand human intelligence and behavior. Deadline December 1, 2026. mindcore.sas.upenn.edu/post-doctora...

Nice real-world example of plausible deniability creating moral wiggle room: conservative MPs secretly vote for a far-right candidate but publicly claim to have abstained: 8 claimed abstentions vs 5 actual. Group-level dishonesty is evident, but individual MPs can hide behind plausible deniability.

New preprint with Julian Garcia & @tobyhandfield.bsky.social 🧵 We tested 1,048,576 moral systems of indirect reciprocity, each pairing a strategy (how to act) with a social norm (how to judge others), across all prisoner's dilemmas, snowdrift games and stag hunts. arxiv.org/abs/2610.03832 1/6

Every AI/HCI paper I review now just sounds like this.

Job alert! More info on how to apply is available in the link shared below. Please help me circulate this information broadly 🙏 (1/2)

Not to brag, but I've been working with the author of #9 on this list (the fantastic @oliviermorin.bsky.social ) for years! This is exactly the kind of piece I've been missing since edge.org died out.. www.nytimes.com/2026/10/05/s...

Very cool project by Cédric Perret (Université de Lausanne): a flexible Julia package to model evolutionary dynamics github.com/CedricPerret...

Gallicagram s'embourgeoise : on a obtenu dix mille euros de la MSH Paris Saclay ! On vous prépare des merveilles pour la présidentielle, vous n'êtes pas prêts 🎶

Pleased to announce the publication of the second edition of 'From Questions to Knowledge: Data Analysis for Psychology and Behavioural Science Using R' mybook.to/questionstok...

Why human societies adopt rigid moral rules: The efficiency–robustness trade-off 
🚨Work by Julien Lie-Panis, Léo Fitouchi, Nicolas Baumard & Jean-Baptiste André

A second Ig Nobel Prize winner! 🏆 Congratulations to Jaimie Krems, Rebecka Hahnel-Peeters, Laureon Merrie, Keelah Williams, and Daniel Sznycer on their 2026 Ig Nobel Peace Prize! 🏆👏 Read the award-winning research in Evolution and Human Behavior: www.sciencedirect.com/science/arti...

Are you into mathematical modelling of ecological and evolutionary systems? Look at this job ad for a senior lecturer in Lund. I've visited many times, splendid compact city, splendid department! lu.varbi.com/en/what:job/...

New Paper out now in PNAS: Is cousin marriage associated with greater or lower exposure to physical intimate partner violence and coercive control? www.pnas.org/doi/10.1073/...

Did Nazi marches persuade or polarize voters? In 1932 Hamburg, full exposure raised Nazi vote share by ~1 pp (18% of citywide gain), but only by widening divides: support rose in Nazi-leaning areas and fell in opposition areas. Spillovers made up ~half the effect. academic.oup.com/jeea/advance...

I’m now @grinnellcollege.bsky.social in Anthropology where I’ll be offering a series of new courses on human #evolutionary social #science & #biologicalanthropology and launching a new lab to support student research and expand my research program. 🧪 #HBES 🌾💎 #Grinnell

Looking for an Associate Prof position? Interested in behavioural ecology & cultural evolution? Come join us at the Dpt of Ecology and Evolution in Lausanne🇨🇭 @dee-unil.bsky.social @unil.bsky.social! Great department & great place to live. Pls RP. Apply here: wwwfbm.unil.ch/releve/appli...

Out now in PNAS. www.pnas.org/doi/10.1073/... Thank you to all peers and colleagues who provided invaluable feedback during the process!

A Demographic Theory of Similarity-Biased Social Learning. Now out in PNAS, led by the incomparable @apvelilla.bsky.social . We use modeling to explore conditions for the (cultural) evolution of parochial (and anti-parochial) learning biases. www.pnas.org/doi/10.1073/...

🚨 PNAS paper: "Indirect reciprocity undermines indirect reciprocity destabilizing large-scale cooperation" w/ Eric Schnell How do we achieve global cooperation on climate or conflict reduction? The problem isn't selfishness as much as it is cooperation itself - at a smaller scale. 1/

No Evidence of Experimenter Demand Effects in Three Online Psychology Experiments

🍄 New paper out in PLOS Computational Biology! 🍄 I, and others, have previously drawn a comparison between the classic “cost-avoidance” argument for social learning and the central idea of resource rationality... (1/8)

1/4 In today's funding climate, every grant and fellowship matters. Based on feedback from our GSAC Community Check-In Survey, we're building a growing hub of graduate & postdoctoral funding opportunities and job boards to make them easier to find. 🧵

3/4 Our graduate funding database was compiled by @prothamamanna.bsky.social. The postdoctoral funding & job board resources were originally compiled by @dieterlukas.fediscience.org.ap.brid.gy and are shared with permission.

Why do human societies adopt rigid moral rules? People often have legitimate reasons for failing to cooperate, yet those reasons are often opaque, allowing opportunists to disguise selfishness as justified hardship. Rigidity preserves cooperation when trust is fragile www.pnas.org/doi/10.1073/...

The Causality in Cognition Lab is pumped for #CogSci2026 🇧🇷

You roll a fair die, hoping to get a 6. If you are successful, did you *intentionally* roll a 6? In a new paper, I explain why people hesitate to call lucky outcomes intentional:🧵 direct.mit.edu/opmi/article...

Want to do a PhD to work on models of opinion dynamics and the inequalities of information flow, with an emphasis on climate change and climate policy? Apply by October 15 to work with Ago Merico and myself, based at @leibniz-zmt.de in Bremen, Germany. www.leibniz-zmt.de/en/vacancies...

"... rigid moral rules act as a social technology: they trade efficiency for robustness, extending the reach of reputation-based cooperation."

Why do human societies adopt rigid moral rules? Our new paper, led by @jliep.bsky.social, proposes a new model in PNAS @pnas.org! www.pnas.org/doi/10.1073/...

I'm super excited to have joined @ubcmath.bsky.social and @ubcmicroimmuno.bsky.social !! Please get in touch if you might be interested in graduate studies or postdoctoral research opportunities!

Have ideas for your own, independent research program in Theoretical Biology? Then come and join us as a Group Leader at the @mpi-evolbio.bsky.social in Plön, Germany!

📣 I'm hiring! Two positions (PhD student & Postdoc) in my ERC project Macroevolution of European Literature. Let's study the cultural evolution of literature using massive data 📚📈 📍Frankfurt | Apply by August 15 Details: www.aesthetics.mpg.de/en/career/jo... Please repost to help spread the word!