Polgár and his wife considered various possible subjects in which to drill their children, "including mathematics and foreign languages," but they settled on chess. They had three daughters together, Susan, Sofia, and Judit, whom Polgár home-schooled, primarily in chess but also in Esperanto, German, Russian, English, and high-level math. He and Klara married in the USSR, whereupon she moved to Hungary to be with him. In reading those biographies, he had "identified a common theme-early and intensive specialization in a particular subject." Certain that "he could turn any healthy child into a prodigy," he "needed a wife willing to jump on board." In 1965 Polgár "conducted an epistolary courtship with a Ukrainian foreign language teacher named Klara." In his letters, he outlined the pedagogical project he had in mind. He concluded that if he took the right approach to child-rearing, he could turn "any healthy newborn" into "a genius." In 1992, Polgár told the Washington Post: "A genius is not born but is educated and trained….When a child is born healthy, it is a potential genius." He later recalled that "when I looked at the life stories of geniuses" during his student years, "I found the same thing.They all started at a very young age and studied intensively." He prepared for fatherhood prior to marriage, reported People Magazine in 1987, by studying the biographies of 400 great intellectuals, from Socrates to Einstein. He studied intelligence when he was a university student. Frankenstein" and viewed by his admirers as "a Houdini", noted Peter Maas in the Washington Post in 1992. Polgár's experiment with his daughters has been called "one of the most amazing experiments…in the history of human education." He has been "portrayed by his detractors as a Dr. He is also considered a pioneer theorist in child-rearing, who believes "geniuses are made, not born". He has written well-known chess books such as Chess: 5334 Problems, Combinations, and Games and Reform Chess, a survey of chess variants. Judit is widely considered to be the greatest female chess player ever as she is the only woman to have been ranked in the top 10 worldwide, while Zsuzsa became the Women's World Chess Champion. He is the father of the famous Polgár sisters: Zsuzsa, Zsófia, and Judit, whom he raised to be chess prodigies, with Judit and Zsuzsa becoming the best and second-best female chess players in the world, respectively. László Polgár (born ) is a Hungarian chess teacher and educational psychologist.