I was saddened to hear that Gerald Gaus, the world-renowned liberal philosopher, died yesterday. Gaus was a critical developer of a public reason approach to classical liberalism, and powerful exponent of the interdisciplinary research agenda of Philosophy, Politics and Economics. While we met in person only occasionally, he was a significant influence on my approach to understanding the liberal tradition.

His perspective was deeply pluralist. One observation that really struck me from The Order of Public Reason (and that I still grapple with today) was that a society could function more effectively (in fact, might only function at all) when citizens have a range of moral attitudes towards things like rule-following, and especially eagerness to punish rule-breakers. For society to progress, you may need both conservative-inclined individuals to enforce moral norms and liberal-minded people to challenge them when circumstances prompt reform.

He applied this idea of strength through moral diversity to the political system too. On Gaus’s account, one of the strengths of liberal democracy is its ability to shift from conservative to liberal, and left to right, through competitive elections. Social progress cannot follow a straight and obvious path but requires, at different moments, experimentation, innovation, reversal and consolidation. Democracy helps select the dominant mode from a diversity of perspectives.

This depth of pluralism is counter-intuitive within the discipline of normative political theory that increasingly avers a narrow set of ideological commitments as acceptable, and rejects even fairly minor variations in social morality as possessing little or no value. Indeed, the last time I saw Gaus was early this year when he gave an evening talk at the Britain and Ireland Association for Political Thought conference. He presented a model for seeking political compromises among very different moral ideals. His commitment to treating the whole political spectrum as worthy of engagement drew a few heckles. The prospect of engaging with Trump supporters, for example, evidently nauseated some of the audience. Gaus was the very model of the liberal interlocutor, ignoring the hostility, and responding with grace, civility and ideas for going forward productively.

His approach to scholarship and discussion embodied his commitment to liberal toleration and the fusion of ethical horizons. That’s how he will be remembered.