Brief History of Philosophy



1800 bc - 300 bc

The beliefs of many cultures/people characterized by their uncritical acceptance of stories that explain natural phenomena. Written mythologies date back to 2800 bc.

Natural Philosophers/Pre-Socratics

600 bc - 370 bc

These early philosophers helped to transition from unchecked mythology to critical thought emphasizing reason.

Big Three Greek Philosophers

430 bc - 322 bc

The most important philosophers of the ancient world came from this short time period in Athens.


323 bc - 420 ad

A period of time marked be the decline of Greek culture and a fusion of the cultures/beliefs of a multitude of kingdoms.

Medieval Age

400 ad - 1400 ad

A time period marked by the emphasis on Christian theology and some remaining/selected Greek philosophy/thought.


1400 ad - 1600 ad

The years following the Medieval age, known as a "rebirth" of many of the cultural influences of the Hellenistic age. A time of rapid cultural, religious, political evolution.

The Scientific Revolution

1543 - 1727

The period of time where the intellectual emphasis on rationalism transfers to empiricism. Discoveries are made primarily through the sense and induction.


1600 - 1725

A period of time developed after the Renaissance known for a unique development of the arts.

The Enlightenment

1650 - 1789


1770 - 1848

The Modern World

1850 - 1970



1391 bc - 1271 bc

The cultural father of the Jewish people (and ultimately Christian and Muslim). His writings stand as the basis for Jewish culture, history and spirituality - comprised as the Torah.

Thales of Miletus

624 bc - 546 bc

Studied the earth and it's processes. He asked: "What is the basic substance of the cosmos?" He reasoned: "It must be a few things: essential to life, capable of motion, and capable of change." He thus concluded water was the basic element.

Siddhārtha Gautama

563 bc - 483 bc

Also known as the Buddha, Siddhārtha offered enlightenment by freeing oneself from the desire which will ultimately leads to suffering. The Buddha also uniquely challenged authority in demanding the fallibility of scriptures. Truth was determined by experience and praise from the wise - which was a step away from mythology.


535 bc - 475 bc

Heraclitus trusted his senses and used reason to explain why things change when they come from a common root. He determined that "everything flows" or is in a constant state of change.


515 bc - 445 bc

Parmenides realized that his reason can come in conflict with his senses. He was the earliest to choose his reason over the senses. Thus he determines that they world is not in change - our sense are deceiving.


490 bc - 430 bc

Empedocles solves the dilemma created by Heraclitus and Parmenides: The world is made of something, yet the world changes. How can something randomly change? Empedocles determines that there must be more than one (four) root elements.


469 bc - 399 bc

Socrates takes speculative reasoning to new levels. He determines that he is the wisest man because he knows what everyone else does not, that we (he) know(s) nothing. At the core of his contribution is his belief that all people have common ability to apply reason to discover truth. Thus, he spent his life asking questions and allowing this common reasoning to discover truths through conversation. Socrates ultimately dies for his ideas which were deemed dangerous by the politicians of Athens. His legacy lived on through his students, including Plato and the early Cynics and Stoics.


460 bc - 371 bc

Democritus takes Empedocles one step further. He determines that the universe is made up of small, indivisible building blocks - like legos. These building blocks come together to create material things. This is the early birth of the "atom" (Greek for "uncuttable").


427 bc - 347 bc

Plato was the greatest philosopher-student of Socrates. His impact was vast and was one of the main authors of Socrates' ideas. He started the greatest school of philosophy in Athens, the Academy. In addition to his scholastic contributions, he answered the question of what is temporal and what is eternal. To Plato, all material is finite and thus "flows" or changes (i.e. dies, decomposes, etc). What we sense then "flows". He determined that material things must come from "something" that reminds material to compose in one way and not another (e.g. a horse and not a crocodile). This "something" must be eternal and Plato called it the form. Thus, a pine cone is finite/temporary while the concept of the circle that it mimics is eternal. We sense such concepts with our reason, making reason eternal. The eternal was more important to Plato than the things that "flow" or change. Reason is how we access the eternal. Thus, reason is more important sense perception - this belief is the core of "rationalism". Plato's legacy was continued by the advancements of his student, Aristotle.

Diogenes of Sinope

404 bc - 323 bc

Diogenes is probably the most apparent example of Cynic philosophy. Stories recall that Diogenes lived in a ceramic bin on the side of the road with very few material possessions. Cynics held that happiness is not found in power, materials or wealth. This stance caused cynics to become calloused to the pains and pleasures of life. It was Diogenes who was offered anything he desired from Alexander the Great, he replied with the request the Alexander steps to the right so the sun would shine on him.


384 bc - 322 bc

Alexander the Great

356 bc - 323 bc

The Macedonian king and student of Aristotle known for expanding the Greek kingdom to it's greatest reach. His death signals the beginning of Hellenism.


341 bc - 270 bc

Father of the Epicureans (or hedonists) and focused on how to achieve true happiness. Epicurus agreed with Democritus that we are made of atoms that will be returned to the earth when we die. Thus, he decide that living for pleasure was the meaning of life. This is concisely summed in the statement, "The gods aren’t to be feared. Death is nothing to worry about. Good is easy to attain. The fearful is easy to endure."

Zeno of Citium

332 bc - 265 bc

Jesus of Nazareth

5 bc - 33 ad

Jewish teacher who claimed deity. Transformed the Jewish belief in a king that would restore the Jewish state into a distinctly spiritual message. Political restoration or salvation was exchanged for a spiritual restoration. The teaching of Jesus would be combined with a set of Greek philosophers to develop Christian theology in the Medieval years and beyond.


205 ad - 270 ad

Augustine of Hippo

354 ad - 430 ad


570 ad - 632 ad


1126 ad - 1198 ad

Thomas Aquinas

1225 ad - 1274 ad

Nicolaus Copernicus

1473 - 1543

Developed the most advanced heliocentric description of our solar system.

Sir Francis Bacon

1561 - 1626

Among other things, Bacon made new developments for Aristotle's logic and the scientific method.

Galileo Galilei

1564 - 1642

Among other things, Galileo developed theories about celestial bodies that upset the social and religious establishment.

Thomas Hobbes

1588 - 1679


1596 - 1650

John Locke

1632 - 1704

Isaac Newton

1643 - 1727

By building on the findings of previous thinkers (especially Kepler and Galileo), Newton developed basic formulaic laws for the both planetary science and the universe. Contributed a work ethic of rigorous experimentation.

George Berkeley

1685 - 1753


1694 - 1778

David Hume

1711 - 1776

Immanuel Kant

1724 - 1804

Karl Marx

1818 - 1883

Sigmund Freud

1856 - 1939