Westernizer

Westernizers (; ) were a group of 19th-century intellectuals who believed that Russia's development depended upon the adoption of Western European technology and liberal government. In their view, western ideas such as industrialisation needed to be implemented throughout Russia to make it a more successful country. In Russian the term was known as "zapadnichestvo" (зáпадничество), which can be translated as "westernism", and its adherents were known as the "zapadniki", westernists in English. 
In some contexts of Russian history, "zapadnichestvo" can be contrasted with Slavophilia. Latter's proponents argued that the West should adopt Russian cultural values, rather than the other way around.
In modern usage, especially in the developing world, the term can refer to supporters of Western-style economic development.
Leaders.
A forerunner of the movement was Pyotr Chaadayev (1794-1856). He exposed the cultural isolation of Russia, from the perspective of Western Europe, and his "Philosophical Letters" of 1831. He cast doubt on the greatness of the Russian past, and ridiculed Orthodoxy for failing to provide a sound spiritual basis for the Russian mind. He extolled the achievements of Europe, especially in rational and logical thought, its progressive spirit, its leadership in science, and indeed its leadership on the path to freedom.
Vissarion Belinsky (1811-1848) was the dominant figure. He worked primarily as a literary critic, because that area was less heavily censored than political pamphlets. He agreed with Slavophiles that society had precedence over individualism, but he insisted the society had to allow the expression of individual ideas and rights. He strongly opposed Slavophiles on the role of Orthodoxy, which he considered a retrograde force. He emphasized reason and knowledge, and attacked autocracy and theocracy. He had a profound impact on the younger generation. 
Alexander Herzen (1812-1870), was the son of a nobleman who promoted Belinsky's ideas after his death in 1848. He was influenced by Voltaire, Schiller, Saint-Simon, Proudhon, and especially Hegel and Feuerbach. Herzen started as a liberal but increasingly adopted socialism. He left Russia permanently in 1847, but his newsletter " Kolokol " published in London from 1857 to 1867, was widely read. Herzen combined key ideas of the French Revolution and German idealism. He disliked bourgeois or middle-class values, and sought authenticity among the peasantry. He agitated for the emancipation of the Russian serfs, and after that took place in 1861 he enlarged his platform to include common ownership of land, government by the people and stronger individual rights.
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