Isaiah Berlin (1909 - November 5 1997) was a political philosopher and historian of ideas, born in Riga, Latvia.

Fellow of All Souls College, only the second Jew elected a fellow in Oxford University. First President of Wolfson College, Oxford. Chichele Professor of Social and Political Theory at Oxford. President of the British Academy.

He arrived in Britain in 1919. Berlin was awarded the Order of Merit in 1957, and also received many other honours.

His famous essay "Two Concepts of Liberty" in which he distinguished between positive and negative liberty, also called positive and negative freedom, has informed much debate on liberty.

Isaiah Berlin died in Oxford, England

Major works:

• "Karl Marx: His Life and Environment,"
• "Four Essays on Liberty,"
• "Against the Current: Essays in the History of Ideas,"
• "Concepts and Categories,"
• "Russian Thinkers,"
• "Personal Impressions,"
• "The Crooked Timber of Humanity: Chapters in the History of Ideas,"
• "The Sense of Reality: Studies in Ideas and their History,"
• "The Roots of Romanticism,"
• "Three Critics of the Enlightenment: Vico, Hamann, Herder"