It is likely the case that Geuss is not at his all-time best here, in simply pointing out that there is in fact no “ideal speech situation.” But there is a reason why his impatient attacks upon idealist or (what he calls) “ethics first” accounts of political legitimacy find their mark — if Habermas is right about how we need to think about democratic socio-political legitimacy, then what is presently happening across mature Western democracies should be impossible. How is that this supposed set of rational commitments on the part of modern persons is so clearly in the process of collapsing?

Guess’ attempt to inject some realism into the way that we understand the legitimacy of liberal democratic institutions is thus urgently necessary. The argument between Geuss and Habermas, when maximally reconstructed, invites a Habermasian regression all the way back to Legitimation Crisis. It is really a variant of an old argument, banished during the heyday of postwar Western confidence, but now sprung back to life. In principle its the same fight Habermas has with Weber about legitimacy, and also with Niklas Luhmann about the uncoupling of system integration and social integration. The best way to honor Habermas at 90 is not to get huffy about ruining his fete. We need to urgently identify the precise nature of the legitimation crisis unfolding under conditions of advanced technological capitalism.