Gregory M. Reichberg

Research Professor

Gregory M. Reichberg
Email: greg.reichberg@prio.org
Work phone: +47 22 54 77 53
Mobile phone: +47 40 28 62 22
Twitter: @GregReichberg
CV: Download CV

Research Interests

International ethics, artificial intelligence, religion and politics,  moral philosophy in the tradition of Thomas Aquinas

Background

Gregory M. Reichberg is Research Professor at the Peace Research Institute Oslo (PRIO).

He leads Warring with Machines: Military Applications of Artificial Intelligence and the Relevance of Virtue Ethics, a four-year project funded by the Research Council of Norway's Research Programme on the Cultural Conditions Underlying Social Change (SAMKUL). 

His writings include a monograph Thomas Aquinas on War and Peace (Cambridge University Press, 2017), named an "Outstanding Academic Title 2017" by Choice magazine.  

He has also published several co-edited volumes, including Robotics, AI, and Humanity: Science, Ethics, and Policy (Springer, 2021); Religion, War, and Ethics: A Sourcebook of Textual Traditions (Cambridge University Press, 2014); World Religions and Norms of War (United Nations University Press, 2009); and The Ethics of War: Classic and Contemporary Readings (Blackwell Publishing, 2006). 

His recent publications include a co-authored book chapter "AI in Cyber Operations: Ethical and Legal Considerations for End-Users (in Artificial Intelligence and Cybersecurity, Springer, 2023); "Applying AI on the Battlefield: The Ethical Debates" (with Henrik Syse), in Robotics, AI, and Humanity (Springer, 2021); "Philosophical Debate on Deterrence," in Forbidden: Receiving Pope Francis's Condemnation of Nuclear Weapons (Georgetown University Press, 2023), and "From the Nuclear Family to the Family of Nations: Exploring the Analogy," in The Family as Relational Good: The Challenge of Love (Libreria Editrice Vaticana, 2023).  

From 2012-2020 he headed the Oslo-based Research School on Peace and Conflict, and from 2009-2012 he was director of the PRIO Cyprus Centre in Nicosia, where he coordinated research and dialogue activities on the search for a political settlement to the island's division. 

In 2021 he was appointed consultor to the Holy See's Dicastery for Promoting Integral Human Development, headquartered in Vatican City. His contribution focuses on disarmament, the ethical implications of new military technologies, and broader issues of war and peace.

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Events

PRIO started tracking events online in 2007. This listing is not complete. Past events may be mentioned in our news archive.

Recent Publications

Reichberg, Gregory M.; Henrik Syse; Kirsi Marjaana Helkala; James Cook; George R. Lucas Jr. & Frank Pasquale (2023) AI in Cyber Operations: Ethical and Legal Considerations for End-users, in Artificial Intelligence and Cybersecurity: Theory and Applications. Cham (Switzerland): Springer (185–206).
Reichberg, Gregory M.; & Eric Stollenwerk (2022) Trust and Fairness: Ethical Dilemmas in the Iran Nuclear (JCPOA) Negotiations, FAIR Case Brief, 8. Oslo: PRIO.
Reichberg, Gregory M. (2022) Note doctrinale sur la guerre juste. À propos de Fratelli tutti [Doctrinal note on just war: A propos of Fratelli Tutti], La Revue Thomiste 122(3): 439–466.

All Publications

Peer-reviewed Journal Article

Reichberg, Gregory M. (2022) Note doctrinale sur la guerre juste. À propos de Fratelli tutti [Doctrinal note on just war: A propos of Fratelli Tutti], La Revue Thomiste 122(3): 439–466.
Reichberg, Gregory M. (2020) Scholastic Arguments for and against Religious Freedom, The Thomist: a Speculative Quarterly Review 84(1): 1–50.
Reichberg, Gregory M. (2019) Restrictive versus Permissive Double Effect: Interpreting Aquinas, Proceedings of the American Catholic Philosophical Association 91(1): 211–223.
Reichberg, Gregory M. (2018) Reframing the Catholic Understanding of Just War, Journal of Religious Ethics 46(3): 570–596.
Reichberg, Gregory M. & Henrik Syse (2018) Threats and Coercive Diplomacy: An Ethical Analysis, Ethics and International Affairs 32(2): 179–202.
Reichberg, Gregory M. (2018) Journet on the Impossibility of Christian Holy War, Nova et Vetera 16(2): 511–541.
Reichberg, Gregory M. (2017) Jacques Maritain: Christian Theorist of Non-Violence and Just War, Journal of Military Ethics 16(4): 220–238.
Reichberg, Gregory M. (2016) Jacques Maritain, l'Espagne, et la guerre sainte [Jacques Maritain, Spain, and Holy War], Revue thomiste 115(2): 215–233.
Reichberg, Gregory M. (2013) The Moral Equality of Combatants - A Doctrine in Classical Just War Theory?, Journal of Military Ethics 12(2): 181–194.
Reichberg, Gregory M. (2012) Discontinuity in Catholic Just War Teaching? From Aquinas to the Contemporary Popes, Nova et vetera 10(4): 1073–1097.
Reichberg, Gregory M. (2012) Legitimate Authority: Aquinas’s First Requirement of a Just War, The Thomist 76(3): 337–369.
Reichberg, Gregory M.; Henrik Syse & Endre Begby (2012) The Ethics of War. Part I: Historical Trends, Philosophy Compass 7(5): 316–327.
Begby, Endre; Gregory M. Reichberg & Henrik Syse (2012) The Ethics of War. Part II: Contemporary Authors and Issues, Philosophy Compass 7(5): 328–347.
Reichberg, Gregory M. (2011) Aquinas' Moral Typology of Peace and War, Review of Metaphysics 64(1): 467–487.
Reichberg, Gregory M. (2010) Aquinas on Battlefield Courage, The Thomist 74(3): 337–368.
Reichberg, Gregory M. (2010) Thomas Aquinas on Military Prudence, Journal of Military Ethics 9(3): 262–275.
Reichberg, Gregory M. (2010) Thomas Aquinas Between Just War and Pacifism, Journal of Religious Ethics 38(2): 219–241.
Reichberg, Gregory M. (2007) Preventive War in Classical Just War Theory, Journal of the History of International Law 9(1): 3–33.
Reichberg, Gregory M. (2005) Aquinas on Defensive Killing: A Case of Double-Effect?, The Thomist 67(3): 341–370.
Reichberg, Gregory M. (2002) Just War or Perpetual Peace?, Journal of Military Ethics 1(1): 16–35.
Reichberg, Gregory M. (2002) Is There a ‘Presumption Against War’ in Aquinas’s Ethics?, The Thomist 66(3): 337–367.
Reichberg, Gregory M. (2002) Beyond Privation: Moral Evil in Aquinas’s De malo, Review of Metaphysics 55(3): 731–764.
Syse, Henrik & Gregory M. Reichberg (2002) Humanitarian Intervention: A Case of Offensive Force?, Security Dialogue 33(3).
Reichberg, Gregory M. (2001) Rettferdig krig eller evig fred? [Just war or perpetual peace?], Norsk statsvitenskapelig tidsskrift 17(2): 196–220.
Reichberg, Gregory M. (2001) Rettferdig krig eller evig fred? [Just war or perpetual peace?], Norsk statsvitenskapelig tidsskrift 17(2): 196–220.
Syse, Henrik; & Reichberg, Gregory M. (2000) Protecting the Natural Environment in Wartime: Ethical Considerations from the Just War Tradition , Journal of Peace Research 37(4): 449–468.
Reichberg, Gregory M. & Henrik Syse (2000) Ethics of War and Peace: An Introduction, Journal of Peace Research 37(4): 419–420.

Monograph

Reichberg, Gregory M. (2017) Thomas Aquinas on War and Peace. New York: Cambridge University Press.

Book Chapter

Reichberg, Gregory M.; Henrik Syse; Kirsi Marjaana Helkala; James Cook; George R. Lucas Jr. & Frank Pasquale (2023) AI in Cyber Operations: Ethical and Legal Considerations for End-users, in Artificial Intelligence and Cybersecurity: Theory and Applications. Cham (Switzerland): Springer (185–206).
Reichberg, Gregory M. & Henrik Syse (2021) Applying AI on the Battlefield: The Ethical Debates, in von Braun, Joachim; Margaret S. Archer; Gregory M. Reichberg; & Marcelo Sánchez Sorondo, eds, Robotics, AI, and Humanity: Science, Ethics, and Policy. Cham: Springer (147–159).
Reichberg, Gregory M. (2020) Human Nature, Peace, and War, in Ronald Edsforth, ed., A Cultural History of Peace in the Medieval Age, 800-1450. London: Bloomsbury Publishing (33–49).
Reichberg, Gregory M. & Henrik Syse (2019) Large-Scale Investment Management: The Peace Potential of a Sovereign Wealth Fund, in Miklian, Jason; Rina M. Alluri; & John Elias Katsos, eds, Business, Peacebuilding and Sustainable Development. Abingdon: Routledge (182–200).
Reichberg, Gregory M. (2019) Thomas Aquinas on Battlefield Martyrdom, in Bernhard Koch, ed., Chivalrous Combatants? the Meaning of Military Virtue Past and Present. Baden-Baden: Nomos (95–106).
Reichberg, Gregory M. (2019) Prudential War in the Utopia, in Edward J. Alam, ed., Thomas More’s Utopia, 500 Years On… and Counting. Louaize, Lebanon: Notre Dame University-Louaize NDU Press (70–87).
Reichberg, Gregory M. (2017) Jacques Maritain, Spain, and Holy War, in Joshua Schulz, ed., Engaging the Times: the Witness of Thomism. Washington, DC: Catholic University of America Press (85–100).
Reichberg, Gregory M. (2016) Historiography of Just War Theory, in Lazar, Seth; & Helen Frowe, eds, The Oxford Handbook of Ethics of War. Oxford: Oxford University Press.
Reichberg, Gregory M. (2015) The Morality of Nuclear Deterrence: A Reassessment, in Nebel, Mathias; & Gregory M. Reichberg, eds, Nuclear Deterrence: an Ethical Perspective. Geneva: The Caritas in Veritate Foundation (7–32).
Reichberg, Gregory M. (2015) The Decision to Use Military Force in Classical Just War Thinking, in Johnson, James Turner; & Eric D. Patterson, eds, The Ashgate Research Companion to Military Ethics. Farnham: Ashgate (13–23).
Reichberg, Gregory M. (2014) Catholic Christianity: Historical Development, in Reichberg, Gregory M.; & Henrik Syse, eds, Religion, War, and Ethics: a Sourcebook of Textual Traditions. Cambridge: Cambridge University Press (76–103).
Reichberg, Gregory M. (2013) History of Just War Theory, in Hugh LaFollette, ed., International Encyclopedia of Ethics. Hoboken: Wiley-Blackwell.
Reichberg, Gregory M. (2013) Culpability and Punishment in Classical Theories of Just War, in Lang Jr., Anthony F.; Cian O'Driscoll; & John Williams, eds, Just War: Authority, Tradition, and Practice. Washington, D.C.: Georgetown University Press (157–180).
Reichberg, Gregory M. (2013) Jacques Maritain, in Kristiansen, Ståle Johannes; & Svein Rise, eds, Key Theological Thinkers: from Modern to Postmodern. London: Ashgate (657–668).
Reichberg, Gregory M. (2011) Suárez on Just War, in Daniel Schwartz, ed., Interpreting Suárez. Cambridge, UK: Cambridge University Press (185–204).
Reichberg, Gregory M.; Nicholas Turner & Vesselin Popovski (2009) Norms of War in Cross-Religious Perspective, in Popovski, Vesselin; Gregory M. Reichberg; & Nicholas Turner, eds, World Religions and Norms of War. Tokyo: United Nations University Press (303–315).
Reichberg, Gregory M. (2009) Norms of War in Roman Catholic Christianity, in Popovski, Vesselin; Gregory M. Reichberg; & Nicholas Turner, eds, World Religions and Norms of War. Tokyo: United Nations University Press (142–165).
Reichberg, Gregory M. (2008) "Jacques Maritain", in Moderne Teologi: Tradisjon Og Nytnkning Hos Det 20. Århundrets Teologer. Oslo: (653–665).
Reichberg, Gregory M. (2008) Just War and Regular War: Competing Paradigms, in Rodin, David; & Henry Shue, eds, Just and Unjust Warriors: the Moral and Legal Status of Soldiers. Oxford: Oxford University Press (194–213).
Reichberg, Gregory M. (2008) Jus ad Bellum, in Larry May, ed., War: Essays in Political Philosophy. Cambridge/New York: Cambridge University Press (11–29).
Reichberg, Gregory M. (2007) Is There a ‘Presumption Against War’ in Aquinas’s Ethics?, in Ethics, Nationalism, and Just War: Medieval and Contemporary Perspectives. Washington, DC: (72–98).
Syse, Henrik & Gregory M. Reichberg (2007) Protecting the Natural Environment in Wartime: Ethical Considerations from the Just War Tradition, in Ethics, Nationalism, and Just War: Medieval and Contemporary Perspectives. Washington, DC: (190–217).
Reichberg, Gregory M. (2005) ‘Unterzeichnen Sie oder wir werden Sie bombardieren!’ Zur Ethik der Zwangsdiplomatie [‘Sign or We’ll Bomb!’ Ethics and Coercive Diplomacy], in Globale Gerechtigkeit–Global Justice. Stuttgart, Bad-Cannstatt : (129–149).
Reichberg, Gregory M. (2005) Authority, Just Cause, and the Decision to Invade Iraq, in Ethics, Law and Society. Aldershot: (243–247).
Reichberg, Gregory M. & Henrik Syse (2004) The Idea of Double Effect – in War and in Business, in Responsibility In World Business: Managing Harmful Side-Effects of Corporate Activity. Tokyo: United Nations University Press (17–38).
Reichberg, Gregory M. (2003) Francisco de Vitoria, De Indis and De iure belli relectiones (1557): Philosophy Meets War, in Gracia, Jorge; Gregory M. Reichberg; & Bernard Schumacher, eds, The Classics of Western Philosophy: a Reader's Guide. Oxford: Wiley-Blackwell (197–203).
Reichberg, Gregory M. (2002) The Hard Questions of International Business: Some Guidelines from the Ethics of War, in Business Ethics and Leadership In Action. Cheltenham; Northampton: Elgar (304–318).
Reichberg, Gregory M. (2002) The Intellectual Virtues (Ia IIae, qq. 57–58), in Essays on the Ethics of St. Thomas Aquinas. Washington DC: (131–147).
Reichberg, Gregory M. (2001) Le mal moral d'après le De malo de Thomas d'Aquin [Moral evil in the De malo of Thomas Aquinas], in Le mystère du mal. Péché, souffrance et rédemption. Toulouse: .
Syse, Henrik & Gregory M. Reichberg (1999) Conducting Business Amidst Human Rights Abuses: Some Lessons from the Just War Tradition, in Proceedings of the Tenth Annual Meeting of the International Association For Business and Society. London: SAGE (71–76).
Reichberg, Gregory M. (1999) Ancient and Early Medieval Thinking about Religion, in Philosophy of Religion: a Guide to the Subject. London & Washington DC: (5–11).
Reichberg, Gregory M. (1999) Studiositas, the Virtue of Attention, in The Common Things: Essays in Thomism and Education. Washington, DC: (143–152).

Edited Volume

von Braun, Joachim; Margaret S. Archer; Gregory M. Reichberg; & Marcelo Sánchez Sorondo, eds, (2021) Robotics, AI, and Humanity: Science, Ethics, and Policy. Cham: Springer.
Reichberg, Gregory M.; & Henrik Syse, eds, (2014) Religion, War, and Ethics. New York: Cambridge University Press.
Reichberg, Gregory M.; Vesselin Popovski; & Nicholas Turner, eds, (2009) World Religions and Norms of War. Tokyo, New York, Paris: United Nations University Press.
Syse, Henrik; & Gregory M. Reichberg, eds, (2007) Ethics, Nationalism, and Just War: Medieval and Contemporary Perspectives. Washington, DC: The Catholic University of America Press.
Reichberg, Gregory M.; Henrik Syse; & Endre Begby, eds, (2006) The Ethics of War: Classic and Contemporary Readings. Oxford: Blackwell.
Gracia, Jorge; Bernard Schumacher; & Gregory M. Reichberg, eds, (2003) The Classics of Western Philosophy: A Reader’s Guide. Oxford.

Non-refereed Journal Article

Syse, Henrik & Gregory M. Reichberg (2004) Introduction, Journal of Military Ethics 3(2): 79–81.
Reichberg, Gregory M. (2003) Legitimate Authority, Just Cause, and the Decision to Invade Iraq, Cardiff Centre for Ethics, Law and Society.
Syse, Henrik & Gregory M. Reichberg (2001) What Kind of War? 11 September and Beyond, Security Dialogue 32(4): 499–501.

Popular Article

Reichberg, Gregory M. (2004) Preemptive War: What would Aquinas say?, Commonweal, 3 July.
Harpviken, Kristian Berg; Cecilie Hellestveit & Gregory M. Reichberg (2003) Er klasebomber et legitimt virkelmiddel i krig? [Is it Legitimate to Use Clusterbombs in Times of War], Dagbladet, 20 July.
Reichberg, Gregory M. & Henrik Syse (2003) Folkerett og etikk [International Law and Ethics], Dagens Næringsliv, 30 January.
Reichberg, Gregory M. (2001) ‘Dobbel effect’ og sivile tap [‘Double-effect’ and harm to civilians ], Dagbladet, 22 November.

PRIO Report

Reichberg, Gregory M.; & Eric Stollenwerk (2022) Trust and Fairness: Ethical Dilemmas in the Iran Nuclear (JCPOA) Negotiations, FAIR Case Brief, 8. Oslo: PRIO.
Faustmann, Hubert; Ayla Gürel; & Gregory M. Reichberg, eds, (2012) Cyprus Offshore Hydrocarbons: Regional Politics and Wealth Distribution, PRIO Cyprus Centre Report, 1. Nicosia: PRIO Cyprus Centre.

Conference Paper

Reichberg, Gregory M. (2005) Just War and Regular War: Competing Paradigms, presented at Workshop on the Moral Asymmetry of Combatants, Oxford University, 23–25 June .
Syse, Henrik & Gregory M. Reichberg (2001) Subsidiarity Applied to Defense, presented at Federalism and Subsidiarity, 3d meeting of the Euro Conferences on Global Justice, University of Florence, 1 January.
Reichberg, Gregory M. (2001) “Legitimate Authority” Under Fire, presented at the conference ‘Military Obedience: Ethical, Military and Legal Perspectives’, Brussels, Royal Military Academy, 1 January.
Reichberg, Gregory M. (2001) Jacques Maritain and the Ethics of Civil War, presented at the American Maritain Association annual meeting, Baca Raton, Florida, 1 January.
Reichberg, Gregory M. (2001) The Ethical Downside of Wealth, presented at the International Finance Research Forum, Edinburgh, Scotland, 1 January.

PRIO Paper

Carrozza, Ilaria; Nicholas Marsh & Gregory M. Reichberg (2022) Dual-Use AI Technology in China, the US and the EU: Strategic Implications for the Balance of Power, PRIO Paper. Oslo: PRIO.

Report - Other

Nebel, Mathias; & Gregory M. Reichberg, eds, (2015) Nuclear Deterrence: An Ethical Perspective, Caritas in Veritate Foundation Working Papers, 6. Geneva: The Caritas in Veritate Foundation.

Report - External Series

Reichberg, Gregory M. (2022) Human Fraternity in Cyberspace: Ethical Reflections on the Challenges and Opportunities, WP-13. Charitas in Veritate Foundation.

Book Review

Reichberg, Gregory M. (2003) Review of Washington et le monde: Dilemmes d'une superpuissance, in Ethics & International Affairs 17(2): 131–135.
Reichberg, Gregory M. (2003) Review of American Empire: The Realities and Consequences of U.S. Diplomacy, in Ethics & International Affairs 17(2): 131–135.

Blog Posts

Diplomacy Isn’t Delusional

Posted by Gregory M. Reichberg, Stein Tønnesson & Henrik Syse on Thursday, 2 February 2023

Why it’s wise for Ukraine to engage with an adversary like Putin. Sven G. Holtsmark offers a rebuttal to our December Commonweal article in which we discussed possible negotiations over Ukraine by referencing an ancient Greek account of war on the island of Melos (also posted on the PRIO blog here and here). We appreciate Holtsmark’s ... Read more »

Right on Its Side, but Not Might?

Posted by Gregory M. Reichberg, Stein Tønnesson & Henrik Syse on Tuesday, 3 January 2023

The lessons an ancient Greek war can teach Ukraine today. Ukraine is confronted with a stark choice: fight on through a bitter winter with death raining from above, or initiate negotiations with Russia under unfavorable terms. Two-and-a-half millennia ago, the leaders of the Greek island of Melos confronted a similar ... Read more »

A Pope’s Dilemma

Posted by Ole Jakob Løland & Gregory M. Reichberg on Thursday, 7 April 2022

Pope Francis has condemned the war in Ukraine in strong words. He dismisses the assertion of Putin’s propaganda that it merely involves “military operations,” and instead condemns it as a war that causes “death, destruction, and distress.” But as head of the Catholic church and its diplomatic arm the “Holy ... Read more »

A Daring Peace Prize

Posted by Gregory M. Reichberg on Tuesday, 10 October 2017

In selecting the International Campaign to Abolish Nuclear Weapons (ICAN) for the 2017 Nobel Peace Prize, the Norwegian Nobel Committee has made a daring move. This year’s laureate was the driving force behind the recently concluded Treaty on the Prohibition of Nuclear Weapons. As of last Friday, October 6, the ... Read more »

The Iranian Nuclear Issue

Posted by Gregory M. Reichberg on Thursday, 18 February 2016

I have been tracking the Iranian nuclear issue for about ten years. Important in its own right, this issue also has significant implications for the international agenda on nuclear weapons disarmament. Let it be noted at the outset that the expression in question – “Iranian Nuclear Issue” – is a freighted ... Read more »

Why Not Nuke ISIS?

Posted by Gregory M. Reichberg on Friday, 4 December 2015

Last week I received a call from a journalist doing background research for an article.  The journalist wanted to know whether I thought a nuclear weapon could be used against ISIS. I was admittedly surprised at this question.  But apparently the journalist queried me about this issue because others are ... Read more »

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