Dear student,

Isaiah Berlin (1909-97) is the 20th Century political philosopher. He is popularly known for his essay "Two Concepts of Liberty", delivered on 31 October 1958 as his inaugural lecture as Professor at Oxford University. It is one of Isaiah Berlin's first expressions of his ethical ontology of value-pluralism. In “Two Concepts of Liberty,” Sir Isaiah Berlin argues that there are indeed two concepts, not one, whose name is liberty. Positive Liberty and Negative Liberty - these two concepts came out as boon for the society. They answer the question by themselves.

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