Top 10 People Who Changed the Way Humans Think

#10: Ayn Rand (1905-82)

Ayn Rand is one of the most polarizing thinkers of the 20th century. A Russian émigré turned novelist/philosopher, she preached the gospel of individualism and capitalism. Her works like "The Fountainhead" and "Atlas Shrugged" laid the foundation for her philosophy of Objectivism. Rand rejected altruism and glorified self-interest as a moral duty. Dismissed by many academics, she became an early pop culture thought leader. Her work found a huge audience among business leaders, libertarians, and conservative politicians in the U.S. and U.K. Decades later, her ideas still echo in debates about free markets, regulation, and the role of government. You don’t have to like her to see her impact: Rand helped hardwire modern right-wing politics.

#9: Ibn Sina [aka Avicenna] (980–1037)

Known in the West as Avicenna, Ibn Sina was the ultimate polymath of the Islamic Golden Age. A physician, philosopher, and scientist, Avicenna wrote hundreds of works covering everything from logic and metaphysics to astronomy and medicine. His Canon of Medicine became a standard medical text in Europe and the Middle East for nearly six centuries. In philosophy, he fused Aristotle and Plato with Islamic thought. He influenced everyone from Thomas Aquinas to the great thinkers of The Enlightenment. His belief in reason and systematic study showed that science could thrive across cultures and faiths. By the time Europe was just waking up from the Dark Ages, Ibn Sina had already helped shape the world of reason.

#8: W.E.B. Du Bois (1868-1963)

W.E.B. Du Bois was one of the sharpest minds of his generation. In an America divided by color, he pioneered a new era of thinking about race and society. The first African American to earn a doctorate from Harvard, he went on to co-found the NAACP. He also became a leading intellectual voice in the fight for civil rights. His landmark book "The Souls of Black Folk" introduced the concept of “double consciousness.” He captured the tension of living with a Black American identity. Du Bois believed education, political activism, and cultural pride were the keys to equality. His ideas also inspired decolonization and Pan-African movements abroad, changing how the entire world tackled race and identity.

#7: Karl Marx (1818-83)

Few thinkers have left the world as rattled as Karl Marx did. A German philosopher and economist, he put forward a revolutionary philosophy. History, Marx argued, was driven by class struggle. He believed that capitalism was inherently exploitative. His most famous works, "The Communist Manifesto" and "Das Kapital," laid out a new vision of society. Marx's ideal nation was built on collective ownership instead of private profit. At the time, his ideas were radical. Suppression of his words was widespread but couldn't contain them. Workers’ movements spread across Europe and beyond. Marx’s reframing of politics, philosophy, and history through the lens of power and production appealed to oppressed workers. Another 'love him or hate him' figure, Marx's impact on the 20th century is undeniable.

#6: Adam Smith (1723-90)

If Karl Marx gave us the critique of capitalism, Adam Smith gave us its blueprint. A Scottish economist and philosopher, Smith is best known for "The Wealth of Nations." Published in 1776 — the same year America declared independence — it introduced the notion of what we now call market forces. Smith argued that individuals pursuing self-interest could unintentionally benefit society as a whole. His “invisible hand” would lead a free market to mass prosperity. Limited government intervention and the power of competition were the keys to success. His ideas laid the intellectual foundation for modern economics and shaped policies across the Western world. Today, every debate about capitalism, regulation, or trade owes something to Smith’s vision.

#5: René Descartes (1596-1650)

“I think, therefore I am.” With those five words, René Descartes permanently changed the way humans approach knowledge. Descartes turned doubt into a scientific method: question everything. Peel back every layer until only the undeniable remains. He wanted philosophy to be as rigorous as math. And, on the subject of mathematics, he knew of which he spoke. He created the Cartesian coordinate system, letting algebra and geometry speak the same language. His cool-headed rationalism helped drag Europe from medieval scholasticism toward the Enlightenment. He may have had an ego to match his intellect, but it's hard to argue that it wasn't well-earned.

#4: Isaac Newton (1643–1727)

Gravity was just Isaac Newton’s opening act. In 1687, his "Principia Mathematica" laid out the laws of motion and universal gravitation. He proved that the same force pulling an apple to the ground keeps the Moon in orbit. It was a revelation: the heavens and the Earth were ruled by the same laws. His vision redefined physics for more than two centuries. Humanity came to believe that the universe could be explained through math. Newton also co-invented calculus, revolutionized optics, and built the first practical reflecting telescope. His mind pushed science into the modern age.

#3: Mary Wollstonecraft (1759-97)

For much of human history, 'rights' weren't really a thing. “Might made right.” People - oftentimes, women - were stuck in a cycle of repression. Feminism as a concept didn't really come along until the end of the 18th century. Then Mary Wollstonecraft came along, an English writer and philosopher. Her book "A Vindication of the Rights of Woman" ignited a centuries-long fight for equality. She argued that women were not naturally inferior to men. If they seemed that way, it's only because they lacked the same opportunities. Wollstonecraft insisted that women deserved the same education, access to the work force, and independence as men. At the time, her book was revolutionary. Though she died young, her words lit a fuse that would ignite later feminist movements.

#2: Confucius (c. 551–479 BCE)

Confucius wasn’t born a king or general - he was a mid-level bureaucrat with big ideas. His was a world of constant warfare between Chinese states. So Confucius preached a radical alternative: order through virtue, not violence. He emphasized education, filial piety, and respect for tradition. He made family values a political philosophy. To him, a good ruler governed by example: morality flows downward from the top. Over time, his teachings became the backbone of Chinese statecraft. Dynasties rose and fell, but Confucianism endured. It shaped everything from schools to governments across East Asia. Today, echoes of his thought influence billions of lives.

Before we unveil our top pick, here are a few honorable mentions.

Hypatia of Alexandria (c. 360–415 CE)

A Female Scholar Who Redefined Who Society Allowed to Shape Ideas

Rabindranath Tagore (1861–1941)

His New Indian Voice in Literature & Philosophy Challenged Colonial Narratives

John Locke (1632-1704)

He Pioneered the Concept of Natural Rights, Influencing Both Democracy & Liberal Thought

Ibn Khaldun (1332–1406)

Ahead of His Time, He Analyzed History Through Social Forces

Chinua Achebe (1930–2013)

His “Things Fall Apart” Forced the World to Rethink African Stereotypes

#1: The Classical Greeks (470-322 BCE)

They were history’s greatest teacher-student relay team. Socrates laid the foundation by teaching not what to think, but how to think. His relentless questions forced people to examine their own beliefs. His student Plato built on that method, spinning grand theories about justice, politics, and the nature of reality. Finally came Aristotle, Plato’s student and tutor to Alexander the Great, who tried to catalog the entire world. He wrote on everything from ethics and politics to biology and physics. Where Plato chased ideals, Aristotle dissected the tangible. Even when wrong, their systems provided the scaffolding of Western thought for centuries. Nearly every branch of philosophy, science, and politics traces back to this chain of teacher to student.

Whose ideas do you think aged the best, and whose didn’t stand the test of time? Let us know your favorite thought leaders from throughout history in the comments below.