Explore philosophical research and education at the Leiden Institute for Philosophy. Our scholars study knowledge, ethics and existence, connecting classical and contemporary thought.

How does the development of digital technologies impact society, and law/regulation within that society?

Artin L-functions associated to continuous representations of the absolute Galois group G_K of a global field K capture a lot of information about G_K as well as arithmetic properties of K.

The territories that would make up what is today the Republic of Zambia officially became British in 1891. However, this did not equate to an on-the-ground presence of colonial authority capable of affecting the destiny and daily lives of people.

Months after the case of the abused foster child from Vlaardingen (Zuid-Holland) came to light, many questions still remain. Why was the child not listened to? Marielle Bruning, Professor of Child Law, discussed this with NOS, NPO Radio 1, NRC and Nieuwsuur.

More attention for internationalisation, diversity, but also the mental health of students: that’s what Marleen van Dorst would like to see change. As of 1 September, she will be the new assessor of the Faculty of Science.

Anthropologist Rodrigo Ochigame studies how AI is changing the practice of scientific research. From astrophysics to mathematics to climate science, they find that the adoption of new AI models is raising questions about what counts as reliable scientific evidence.

The proportion of female professors at Dutch universities is increasing, but at a modest rate. At 34.2%, Leiden University is in the top three. These are the results of the Women Professors Monitor for 2025.

With the growth of cybercrime in recent years, there is an urgency to gain insight into the money laundering process and the actors involved. This study focusses on the money laundering process and maps the actors involved in banking malware and ransomware.

Promotor: H.W. Lenstra, Jr., Co-promotor: B. de Smit

This research project explores themes related to the system of close protection and surveillance (Dutch: bewaken en beveiligen) in the Netherlands.

Samen met een groep enthousiaste wetenschappers bezocht ik deze maand verschillende universiteiten en andere kennisinstellingen tijdens een kennismissie in Indonesië.

How do you achieve the structural change needed for a more inclusive university community? What challenges do female staff face in their careers and what does it take to be a woman in a leadership role? This is what over 40 female staff members from the university discussed on International Women’s…

Book project on how European policy is made and implemented, with a focus on how that process can be understood and lead to policy change.

Understanding the evolving landscape of extremism in the 21st century.

Professor Annetje Ottow will be appointed President of the Executive Board of Leiden University on 8 February 2021. She will be the first woman to be appointed to this post at Leiden University.

LUCIS works with Science ON AIR to put its researchers in the spotlight. For that purpose, several online videos of LUCIS members have been produced.

In November, Springer published a book on The Future of Drone Use, edited by dr. Bart Custers, associate professor at eLaw, the Center for Law and Digital Technologies of Leiden University.

Astronomer and Marxist Anton Pannekoek was a remarkable figure. This book aims to study the connections between his life as a socialist theorist and as a pioneering scientist through the prism of Pannekoek's biography.

Contact details and staff overview of the Leiden University Graduate School of Social and Behavioural Sciences.

Acquiring and maintaining public support is frequently cited as an important requirement for governments fighting non-state actors. But how exactly can public support influence the course of counterterrorism campaigns and thereby contribute to an escalation or de-escalation of violence?

On 23 January 2020, Paula Kemp defended her thesis 'Enforced performance of commercial sales contracts in the Netherlands, Singapore and China'. The doctoral research was supervised by Prof. H.B. Krans and Prof. M.H. Wissink (RU Groningen).

Children who lost their fathers in early modern England ran the risk of being sold to the highest bidder. Although Shakespeare wrote about it in his plays, the practice disappeared from collective memory for a long time. University lecturer Lotte Fikkers is bringing it back to light in a new Vidi research…

Having served on the Executive Board for over nine years, the last five of which as Rector Magnificus, Hester Bijl will leave Leiden University at the start of next year. In a new step in her career, she will become Rector Magnificus on the Executive Board of Delft University of Technology (TU Delft)…

The Executive Board has adopted a new Code of Conduct on Integrity for staff. This new code encompasses all the existing regulations within Leiden University, including in the field of research, behaviour towards students and purchasing. 'This Code of Conduct is a very clear statement,' commented Rector…

Professor Sarah de Rijcke will become the new Rector Magnificus on the Executive Board of Leiden University on 15 January 2026. She will succeed Professor Hester Bijl, who will become Rector Magnificus at Delft University of Technology.

The Editors of PAIR are always interested in suggestions for themed editions. Anyone wishing to propose a theme and/or to assist as a ‘guest editor’ should contact one of the editors of PAIR.

Can excessive worrying be reduced via stimulation of the vagus nerve?

Lange tijd wisten we ons thuis in een wereld die we meenden te hebben. Het bestaan in deze vertrouwde wereld vormde onze existentie, die we op een eigenlijke wijze op ons namen. Thans is de wereld echter niet meer wat hij was, en zijn we ook zelf niet meer wie we waren. ‘De wereld is weg’, zo dichtte…

Philosophy of law is concerned with the the foundations of law.

Who were the main artists and producers who generated new forms of popular music? What was the music like that was produced by artists in particular urban settings? How were particular lifestyles articulated to identify new audiences and what does this reveal about the way popular music contributed…

In 2024, many of our students and staff won great prizes and secured important research grants.

Leiden University’s Rector Magnificus, Professor Hester Bijl, has been reappointed for a second term by the Board of Governors.

Research into our history of colonialism and slavery, heart-to-heart conversations at a Keti Koti table, exhibitions, lectures and podcasts that establish the link between present and past. Staff and students participated in the national Slavery Memorial Year in many different ways. What have we learned…

The Royal Holland Society of Sciences and Humanities (KHMW) has appointed five new members from Leiden. Annetje Ottow, Carsten de Dreu, Pancras Hoogendoorn, Ton Schumacher and Maartje van der Woude will be joining the oldest ‘learned society’ in the Netherlands.

In a supplementary decision on 17 May 2022, the Executive Board of Leiden University has concluded that it will publish the titles of seven articles in which there is evidence of malpractice. This concerns a former staff member of the Institute of Psychology. The Executive Board considers it to be in…

As of 1 November 2025, Professor Luc Sels will assume the role of President of Leiden University’s Executive Board.

Digitalisation to achieve sustainable (administrative) justice.

Why are people sometimes unable to change, even if they want to? Why is it so difficult to change political institutions, or to abandon outdated ways of thinking? This book suggests that we can understand the phenomenon of resistance to change in individuals and institutions by returning to Hegel, one…

Much has been said regarding the global flows of information that are characteristic of modernity; it has been frequently stressed that these conduits are so deeply embedded that local or national environments may be imagined as having a global span. Thus, while we are now well aware that the imagination…

The profile area Political Legitimacy brings together researchers from multiple research institutes within Leiden University.

Schuurman examines how Russia is escalating its covert operations against European countries.

In 2012, the Dutch National Coordinator for Security and Counterterrorism and the Dutch Probation Service launched a reintegration project for offenders on probation or parole who were (suspected to be) involved in jihadist extremism or terrorism. The initiative's primary goal was to reduce the chance…