Dyslexia, a learning disorder characterized by difficulty reading, is fairly common. Even so, it was not largely understood until the late 20th century. Even today it can be hard for doctors to diagnose. There are evidence-based treatments which are effective, even for adults with the condition. Given what we know now, many famous people may have had dyslexia, including Leonardo da Vinci, Saint Teresa, Napoleon, Winston Churchill, Carl Jung, Albert Einstein, and Thomas Edison.