Professor of Political Thought and History
Cambridge University


The Time of PossibilityAnnabel Brett

Lecture I
Tuesday, April 22, 2025
4:10 p.m. – 6:15 p.m., Toll Room, Alumni House
with commentary by Melissa Lane

Lecture II
Wednesday, April 23, 2025
4:10 p.m. – 6:15 p.m., Toll Room, Alumni House
with commentary by Kinch Hoekstra and David Dyzenhaus 

Seminar and Discussion with the Commentators
Thursday, April 24, 2025
4:10 p.m. – 6:15 p.m., Toll Room, Alumni House
with commentary by Melissa Lane, Kinch Hoekstra, and David Dyzenhaus  


About Annabel Brett

Annabel Brett is Professor of Political Thought and History at the University of Cambridge and a Fellow of Gonville and Caius College, Cambridge. Trained in Classics, her first position was in the Department of Philosophy at the University of York before returning to Cambridge as a lecturer in the history of political thought in the Faculty of History. Her PhD research, published in 1997 as Liberty, right and nature. Individual rights in later scholastic thought, explored the intersection between constructions of nature and of right across a range of late medieval and early modern sources. That interface remains a central concern in her second monograph, Changes of state. Nature and the limits of the city in early modern natural law (2011), here focusing on the political community rather than human liberty as the key site of negotiation. She has published numerous other articles and papers, many of them devoted to late scholastic thought which she has made an object of particular study. She has a keen interest in translation, having produced translations of two medieval political tracts (including Marsilius of Padua, The Defender of the Peace), and more recently she has become interested in the history of international law, co-editing the interdisciplinary volume History, politics, law. Thinking through the international (2021) with Megan Donaldson and Martti Koskenniemi. She has lectured and presented her research all over the world, and in 2023 was awarded an honorary doctorate by the Faculty of Theology, University of Helsinki.


About the Lectures

‘Law must be formulated with regard to the possible, if its maker wishes to punish a few to some purpose rather than many to no purpose.’ Plutarch, Lives (Solon)

‘A law shall be honest, just, possible, according to nature, according to the custom of the country, appropriate to time and place, necessary, useful.’ Isidore of Seville, Etymologies, Book II

From antiquity through the middle ages to the renaissance and early modern period, the idea that law must be possible for its subjects was a central motif of European legal and political thought. To command the impossible was a key marker of the tyrant. The classic example was Pharoah in the Book of Exodus, ordering the Israelites to make bricks without providing them with the necessary straw. Pharoah was here commanding the physically impossible of the Israelites. But from Plutarch (and indeed Plato) onwards, thinkers were more interested in the psychologically impossible. This could be something so contrary to natural human impulses that people cannot bring themselves to do it without extreme distress. Again, it was held to be a classic feature of tyranny to compel people to perform the repugnant in this way, recognised as a distinctive form of cruelty. Indeed, commanding the physically impossible could folded into this conception through an appreciation of the desperation that such commands induce. Thinkers were also interested, however, in what is psychologically impossible or intolerable based on the customary or cultural habits of a specific population. To legislate against this kind of possibility was also held to be tyrannical. I will call this ‘legislating down’, that is, law needs to bend down to the level of its subjects to be possible for them.

However, early modern thought recognised certain situations in which law could command the impossible. The central case is imminent danger to the commonwealth in time of war or time of plague. Here, citizens can legitimately be required to face death even if their every instinct is to run away; in other words, law can command the virtue of courage. I will call this ‘legislating up’, that is, the law requires citizens to raise themselves above their normal level of possibility. But although everyone agreed on this, they had interestingly different ideas of why it was not tyrannical to do so. There was far less agreement on demands that override customary psychology, partly because early modern legal thought was committed to the idea that changing the law is in general a bad thing. Law is embedded in habits and any change of habits invites lawlessness. Nevertheless, the alteration of religious practices required by the Reformation provoked a heated discussion on how far, and how fast, ecclesiastical law could command people to leave their familiar comfort zone of ritual. A parallel discussion took place in the context of conversion and urbanisation in the Spanish New World. Through all the debates over possibility ran the question of who decides what is intolerable and what is not, with colonial government the acute example of asymmetric decision on the possibility of law.

These Tanner Lectures aim to put this early modern concept of possibility in dialogue with current legal and political thinking. As the above examples show, early modern possibility thinking was centrally related to the question of time – time of emergency, time of continuity, time of change. The two lectures will consider the politics of possibility in two different times that have been the subject of intense debate recently: the time of pandemic and the time of climate change (or climate emergency – the difference is precisely part of those politics). As is well recognised in the literature, both raise key questions for democratic decision-making and for the control of political time. Both have clear parallels in early modern thought, and the lectures will aim to offer a fresh perspective on contemporary dilemmas on that basis.


About the Commentators

Melissa Lane

Class of 1943 Professor of Politics
Princeton University

 


Kinch Hoekstra

Chancellor’s Professor of Political Science and Law
University of California, Berkeley

 


David Dyzenhaus

University Professor of Law and Philosophy and Albert Abel Chair
University of Toronto