René Descartes for Kids: Big Ideas Made Simple

1596-1650France

Descartes tried to doubt everything he could, and found one thing he couldn't doubt: that he was thinking! If he's thinking, he must exist.

Main idea

Cartesian Doubt - Question everything to find what's certain

Famous quote

I think, therefore I am (Cogito, ergo sum)

Key concepts

  • Cartesian Doubt
  • Rationalism
  • Mind-Body Dualism

How to use it today

When learning something, ask: How do I really know this is true?

Fun fact

Descartes created the Cartesian coordinate system (x, y graphs) used in math

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