If we glance at the most important revolutions in history, we see at once that the greatest number of these originated in the periodical revolutions of the human mind.
Source: Limits of State Action, ch. 16, 1792.
-- Wilhelm von Humboldt, (Jun 22 1767-1835), German scholar, philosopher, diplomat, educator; His contribution to the development of language science was highly valued in the 20th century.