Context: The great man theory is a 19th-century idea according to which history can be largely explained by the impact of great men, or heroes; highly influential individuals who, due to either their personal charisma, intelligence, wisdom, or political skill used their power in a way that had a decisive historical impact. The theory was popularized in the 1840s by Scottish writer Thomas Carlyle, but in 1860 Herbert Spencer formulated a counter-argument that has remained influential throughout the 20th century to the present: Spencer said that such great men are the products of their societies, and that their actions would be impossible without the social conditions built before their lifetimes.\n\nQuestion: who developed the great man theory of leadership?
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The relevant sentence in the passage is: The theory was popularized in the 1840s by Scottish writer Thomas Carlyle, but in 1860 Herbert Spencer formulated a counter-argument that has remained influential throughout the 20th century to the present: Spencer said that such great men are the products of their societies, and that their actions would be impossible without the social conditions built before their lifetimes.
So, the answer is Scottish writer Thomas Carlyle.
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