ID W,X,Y and Z

W and her two younger sisters, X and Y, were part of an educational experiment carried out by their father Z, who sought to prove that children could make exceptional achievements if trained in a specialist subject from a very early age. "Geniuses are made, not born," was Z's thesis. He and his wife Klara educated their three daughters at home, with ____ as the specialist subject. The father also taught his three daughters Esperanto. Most of her family eventually emigrated to Israel, but W moved to New York after marrying an American in 1994.

Although W's home was very humble, her father was a man with a unique vision. A trained psychologist, Z, had made a deep study of the childhood origins of genius. The archetypal example was Wolfgang Amadeus Mozart. Already composing at the age of five, he seemed to be the classic case of a child born with special gifts, but Z noted that Mozart's father Leopold, himself an accomplished musician, gave his son early and invaluable schooling in his craft.

Z decided that specialised training was more important than natural talent and he had an astonishing plan that would put his theory to the test.

When W was born in April of 1969, the family experiment was underway.

Z planned to train W in mathematics but, she chose her own future by a happy accident. One day while searching for a new toy, she happened across a ________. Z himself was convinced he could train his daughter to be a genius at anything, as long as she was a willing student.

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