Leonhard Euler

Hello! My name is Leonhard Euler. I'll bet you use some of my ideas every day in your math class. I was born in a beautiful town called Basel, Switzerland, on April 15th, 1707. My father was a pastor, but he also loved mathematics and taught me all about numbers when I was little. I found them so fascinating! When I was just 13 years old, in 1720, I started at the University of Basel. There, I met a brilliant teacher named Johann Bernoulli, who saw that I had a special talent for math and encouraged me to study it.

In 1727, I moved far away to a grand city called St. Petersburg in Russia to work at a new science academy. It was an exciting time! A few years later, in 1734, I married my dear wife, Katharina. While in Russia, I heard about a fun puzzle. The city of Königsberg had seven bridges, and everyone wondered if you could walk across all seven without crossing the same one twice. In 1736, I figured out it was impossible! By solving this puzzle, I created a whole new type of math called graph theory. I also came up with symbols to make math easier for everyone, like using f(x) to describe a function. It’s like creating a secret code that everyone can learn to understand!

After many years in Russia, I moved to Germany in 1741 to work at the Berlin Academy. I worked on all sorts of things there—from the way planets move to how ships sail. I wrote hundreds of articles and books, sharing my ideas with the world. I loved discovering how numbers could explain almost everything, from the smallest drop of water to the biggest star in the sky. Math was like a universal language, and I wanted to share it with as many people as possible.

In 1766, I was invited back to St. Petersburg. Around this time, my eyesight, which had been getting worse for years, failed me, and I became almost completely blind. You might think this would stop me, but it didn't! I had a powerful memory, and I could see all the numbers and equations perfectly in my mind. I would solve problems in my head and dictate my work to my sons and assistants. I was so full of ideas that I actually did some of my best work during this time.

I lived a very full and happy life, surrounded by my family and my beloved numbers. I lived to be 76 years old. Today, people remember me as one of the greatest mathematicians who ever lived. The symbols I created are in math books all over the world, and my ideas help engineers design bridges, scientists understand the universe, and maybe even help you solve problems in your own classroom. I hope my story shows you that with curiosity and determination, you can solve any puzzle you set your mind to.