Jürgen Habermas, born in 1929, is the leading figure of the second generation of critical theory. He worked as Adorno's assistant in the 1950s and later taught at Frankfurt. Where Horkheimer and Adorno had grown deeply pessimistic about reason, Habermas set out to find a firmer foundation for critique, one that could support democracy rather than despair of it.

The public sphere

In The Structural Transformation of the Public Sphere (1962), Habermas described how, in eighteenth-century Britain, France and Germany, a new space for discussion emerged: coffeehouses, salons, reading societies and journals where private individuals came together to debate public matters. In principle, at least, arguments were judged on their merits rather than on the rank of the speaker. This public sphere put pressure on governments to justify themselves before an informed public.

Habermas argued that in the nineteenth and twentieth centuries this public sphere declined. Mass media, advertising, public relations and organized interest groups turned public debate into something closer to a stage show, where opinion is managed rather than formed through argument. Critics, notably Nancy Fraser, replied that the original public sphere excluded women, workers and others, who formed their own counterpublics. Habermas later accepted much of this criticism.

Communicative action

Habermas's major work, The Theory of Communicative Action (1981), distinguishes two kinds of action:

• Strategic action aims at success. You treat other people as means to your goals, influencing them through rewards, threats or manipulation.
• Communicative action aims at mutual understanding. You try to reach genuine agreement with others on the basis of reasons they can accept.

Whenever we speak sincerely, Habermas argued, we implicitly raise validity claims: that what we say is true, that it is right (appropriate given shared norms), and that we are sincere. Any listener can challenge these claims, and the speaker must then back them with reasons. This, for Habermas, is where reason lives: not only in calculation, but in the everyday practice of giving and asking for reasons. That move allowed him to keep the critique of instrumental reason while finding a positive standard to judge society by.

System and lifeworld

Habermas contrasts the lifeworld, the shared background of meanings, traditions and relationships in which people communicate, with systems such as the market and state administration, which coordinate action through money and power rather than understanding. Modern societies need both. The danger he called the colonization of the lifeworld: when the logic of money and bureaucracy invades areas like family life, education and civic life that depend on communication.

Discourse ethics

From this Habermas developed discourse ethics. Its core principle, in paraphrase: a moral norm is valid only if everyone affected by it could agree to it as participants in a free and fair discussion. Such discussion requires that everyone can take part, question any claim and express their needs, with no coercion, so that only the force of the better argument decides. Real discussions never fully meet these conditions, but the ideal gives a standard for judging and improving actual institutions. Habermas later applied it to law and democracy in Between Facts and Norms (1992), defending deliberative democracy: legitimate laws are those that could win the reasoned agreement of citizens.

Habermas's ideas have influenced real institutions, such as citizens' assemblies and public consultations, where randomly chosen or affected people deliberate before a decision is made. Critics doubt that ordinary politics can ever come close to his ideal.

Worked example: deciding about a new road

An invented city council must decide whether to build a highway through an older neighborhood. Watch how Habermas's distinctions apply.

Strategic action: A developer who would profit from the road hires a public relations firm. It runs advertisements promising jobs, quietly funds a citizens' group that appears independent, and lobbies council members in private. The goal is to win, not to persuade by reasons the residents could accept. Meanwhile some opponents spread exaggerated claims about health risks to frighten people.

Communicative action: The council instead holds open hearings. Engineers present traffic data, which residents can question (a truth claim). Residents argue that the plan unfairly burdens their neighborhood while benefiting commuters from elsewhere (a rightness claim). A council member who owns land near the route is asked to step aside, since doubts about her sincerity would undermine trust (a sincerity claim).

Colonization of the lifeworld: If the decision is made purely through money and administrative procedure, with residents' sense of place and community treated as irrelevant, Habermas would say the system has invaded the lifeworld.

Discourse ethics: The test is whether the final decision could be accepted by all affected, including the residents, after a fair discussion. Perhaps a modified route or compensation would pass that test where the original plan would not.

Critics note that real hearings are slow and dominated by those with time to attend. Habermas would agree that the ideal is never fully reached; it serves as a standard for improving actual practice.