Bobbio was a social liberal in the tradition of Piero Gobetti, Carlo Rosselli, Guido Calogero [it], and Aldo Capitini.

Bobbio studied at the Liceo Classico Massimo d'Azeglio, where he met Leone Ginzburg, Cesare Pavese,[3] and Vittorio Foa, who would all become major figures in the culture of the Italian Republic.

In high school Bobbio met Vittorio Foa, Leone Ginzburg and Cesare Pavese, and at the university, he became a friend of Alessandro Galante Garrone [it].

In 1942, under the Fascist regime of Benito Mussolini and during World War II, Bobbio joined the Partito d'Azione ("Party of Action"), illegal at the time, and was imprisoned in 1943 and 1944.

With the party's failure in a post-war Italy dominated by the Christian Democrats, Bobbio left electoral politics and returned his focus to academia.

He was a strong partisan of the Historic Compromise between the Italian Communist Party and the Christian Democrats, and a fierce critic of Silvio Berlusconi.

According to Richard Bellamy, Bobbio was a public intellectual and throughout his life worked on several causes, including the defence of social democracy and supporting nuclear disarmament.

[14] Bobbio defended the view that "the only way a meaningful discussion of democracy, as distinct from all forms of autocratic government, ... is to consider it as characterized by a set of rules (primary or basic) which establish who is authorised to take collective decisions and which procedures are to be applied.