Two Concepts of Liberty

Two Concepts of Liberty was the inaugural lecture delivered by the liberal philosopher Isaiah Berlin before the University of Oxford on 31 October 1958. It was subsequently published as a 57-page pamphlet by Oxford at the Clarendon Press. It also appears in the collection of Berlin's papers entitled Four Essays on Liberty (1969) and was more recently reissued in a collection entitled simply Liberty (2002).

The essay, with its analytical approach to the definition of political concepts, re-introduced the study of political philosophy to the methods of analytic philosophy. It is also one of Berlin's first expressions of his ethical ontology of value-pluralism. Berlin defined negative liberty, as the term "liberty" was used by Thomas Hobbes, as the absence of coercion, or interference with, agents' possible private actions, by an exterior social-body, and as a comparatively recent political ideal, which, Berlin later writes, re-emerged in the late 17th century, after its slow and inarticulate birth in the Ancient doctrines of Antiphon the Sophist, the Cyrenaic discipleship, and of Otanes after the death of pseudo-Smerdis. In an introduction to the essay, Berlin writes:

"As for Otanes, he wished neither to rule nor to be ruled — the exact opposite of Aristotle's notion of true civic liberty... remains isolated and, until Epicurus, undeveloped... the notion had not explicitly emerged".