Albert Einstein

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Einstein's name has become synonymous with genius. This guy is famous for being smart even though most people couldn't even begin to explain his discoveries. He wasn't always a success story, though.

Einstein didn't speak until he was 4 years old. When he was 16, he failed to pass the examination for entrance into the Swiss Federal Polytechnic school located in Zurich. He did manage to graduate from university, but he nearly dropped out after he struggled in many of his courses.