Putting two monads together in thought -- which is the essential meaning of inter-subjectivity in philosophy -- doesn't dissolve the fiction of the abstract individual; in fact, it is based upon it.
Stephen K. White writes in "Reason, Modernity, and Democracy," _The Cambridge Companion to Habermas_, ed. Stephen White (Cambridge: Cambridge UP, 1995):
***** Previous articulations of the idea of a political community of free and equals have foundered on their inability to resolve the conflict between private and public autonomy. Either individual rights are given priority over collective autonomy (as in Kant and liberalism), or collective autonomy is given priority over the individual (as in Rousseau, republicanism, and communitarianism). The problem, according to Habermas, is that both positions are rooted in notions of _subjectivity_, individual or collective. If political theory is rooted instead in a notion of _intersubjectivity_ fleshed out in communicative-rational terms, then we can understand the "equi-primordiality of private and public right [Recht]." This is so because, in Habermas's terms, public autonomy is reconceived as the availability of a differentiated "network" of communicative arrangements for the discursive formation of public opinion and will; and a system of basic individual "rights provides exactly the conditions under which the forms of communication necessary for a politically autonomous constitution of law can be institutionalized."[32]
[32] Habermas, _Faktizitat und Geltung: Beitrage zur Diskurstheorie des Rechts und des demokratischen Rechtstaats_ (Frankfurt: Suhrkamp, 1992) *****
In other words, for Habermas, individuals who are to form "intersubjectivity" are fundamentally abstract individuals, legal persons who are bearers of rights in liberal democracy (not concrete individuals who are ensembles of social relations), who belong to "lifeworlds" of liberal interest groups; in turn, Habermas's (later) works are designed to give a new and more sophisticated legitimation to _Rechtstaats_. (It is in this context that the Serbs become the Other of "intersubjectivity" of a "constitutional community" (_Rechtsgemeinschaft_) as the foundation of the legitimacy of _Rechtstaat_; in Habermas's theory, there is no room for a criticism of imperialism, hence his support of NATO's war on Yugoslavia.)
Habermas has come a long (or short?) way from his earlier sympathy with a socialist project that seeks to go beyond liberalism (in, for instance, _Legitimation Crisis_). In "What Does Socialism Mean Today?" (in _After the Fall: The Failure of Communism and the Future of Socialism_, ed. Robin Blackburn, NY: Verso, 1991), he says: "The liberal interpretation is not wrong. It just does not see the beam in its own eye." He goes further: "With the bankruptcy of state socialism, [welfare state liberalism] is the eye of the needle through which everything must pass." Therefore, Habermas's "rationality" also goes through the eye of the needle, in the process becoming the Reason of the liberal State, ridding itself of reasons to criticize it radically.
Yoshie