Expelled from high school, unable to find a teaching job and stuck working at a government patent office, Albert Einstein nonetheless went on to become one of the greatest scientific thinkers of all time. He ended up using his free time at the Swiss Patent Office to develop his groundbreaking theories on the nature of time and space. Although his early theories paved the way for the atomic bomb, Einstein later became a peace activist, saying, "I know not with what weapons World War III will be fought, but World War IV will be fought with sticks and stones." By the time he died in 1955, he was considered not only the most important scientist but the smartest man of his time.