“Karl Marx ranks as one of the most remarkable thinkers in history - remarkable for the degree to which and the rapidity with which his ideas had an impact on world culture. When I was in high school, the population of the world was 2 billion; by the time I was forty-five the population of the world had increased dramatically. What stunned me, however, was that by that time 2 billion people were living behind the Iron Curtain. By the time I was forty-five, as many people lived under Marxist regimes as had lived in the entire world when I was a teenager.”
― R.C. Sproul, The Consequences of Ideas: Understanding the Concepts that Shaped Our World / Justification by Faith Alone