On April 18, 1955, Albert Einstein died of a ruptured artery. The theoretical physicist had influenced the core of the philosophy of science with the general theory of relativity, which became one of the two pillars of modern physics. Einstein's influence extended beyond the scientific fields he revolutionized, as his strong political and social views have also made him a pop culture icon of intelligence and wisdom.

Here are a few lesser-known facts about Einstein that speak to his character.

He Was A Slow Talker

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Albert Einstein did not speak until comparatively late in childhood, and remained reluctant to talk until about the age of seven. Some argue this was an indication that he had Asperger's syndrome, an autism spectrum disorder that affects language and behavioral development in children.

He Didn't Fail Math

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Despite this widely believed myth, Einstein did not fail math at first. In fact, he excelled in physics and math from a young age and studied calculus while only 12 years old.

He Had His Biggest Ideas In One Year

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In 1905, Einstein published four papers that comprised some of his most significant contributions to physics, all while writing a doctoral dissertation and working as a clerk in the Swiss patent office. Of his four papers, one established the mathematical theory of special relativity, and the other later won him the Nobel prize.

He Didn't Win The Nobel For The Theory Of Relativity

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That Nobel Prize Einstein was awarded wasn't for his paper on the theory of relativity, but in fact for another paper that  explained the photoelectric effect using quantum theory. His more significant discovery of relativity went unrewarded, as it took years to prove one of its key predictions, the lensing effect of gravity.

He Mediated a Hostage Negotiation

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Einstein was a well-known pacifist, and put his beliefs to the test in post-World War I Germany, when radical students at the University of Berlin took the rector and several professors hostage. Einstein was well respected on the campus, so he and Max Born, a German-born pioneer of quantum mechanics, were able to defuse the situation.

He Had An Illegitimate Daughter

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While attending university in Zurich, Einstein had a love affair with a fellow student, Mileva Marić, who would eventually become his first wife. Early in their relationship, however, the couple had a daughter named Lieserl before getting married, and with Mileva giving birth at her parent's home in modern Serbia. After he birth, the couple never spoke about the daughter again, with many speculating that she either died in infancy, or was given up for adoption.

He Was A Womanizer

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Einstein and Marić's marriage eventually came to an end, however, due to Einstein's flirtations and philandering with other women. One of his mistresses, his cousin Elsa, would eventually become his second wife. Einstein continued to have affairs while with Elsa, but she allowed them so long as he kept them quiet.

His Nobel Prize Money Went To A Divorce Settlement

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Einstein's divorce from Mileva Marić was only granted to him on a condition he proposed: That when he eventually won the Nobel Prize for one of his papers, he would give her the award money as settlement. It would take until 1922 before he was awarded the prize and she could collect.

He Was Offered The Presidency of Israel

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In addition to his physics achievements, Einstein was also famous for his political views. He was a lifelong pacifist and advocated against nuclear proliferation after the end of World War II. In 1952, Israeli premier David Ben-Gurion offered Einstein the presidency of the newly established state of Israel, but he turned him down, citing his advanced age.

His Brain Was Stolen

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Einstein had intended to be cremated after his death, but the doctor that performed his autopsy on April 18, 1955 in Princeton, pathologist Dr. Thomas Harvey, had other plans. Having the opportunity to study the brain of one of the great geniuses of the age, he stole 2.7 pounds of Einstein's brain, as well has his eyes, which he gave to Einstein's eye doctor. Harvey moved the brain a number of times and cut it into a number of pieces to be stored in jars, but never got around to studying it. After 43 years, he returned to specimens to Princeton.