The young man's progress through the ranks of academia was steady and swift. After several years in Germany he went on to study in Paris.
The young man was particularly interested in mathematics and medicine, and he decided to write a book on each of them. The mathematical treatise dealt with an original theorem he had formulated, the other book was on the subject of anatomy. Soon he was the darling of the international scientific community.
Inexplicably, however, he began to feel guilty over how he had treated his parents. He took a leave of absence and set out for home.
The long journey gave him time to think. "What good will it do to show my father my books?" he mused. "He has no understanding of such matters. Better I should first go to my father's Rebbe and get his approval. They say that as a young man, Rabbi Shneur Zalman studied geometry and astronomy. If he pronounces them worthy, my father will respect his opinion."
Rabbi Shneur Zalman agreed to see him at once. The Rebbe's door was closed for a long time. When the young man finally emerged he was extremely agitated. It was obvious he was in the midst of an inner battle.
Suddenly, without warning, he grabbed one of his books and threw it into the furnace. A minute later the second one followed. Both were quickly consumed by the flames. Only then did he calm down.
What had happened? Rabbi Shneur Zalman had scrutinized only five pages of the first book when he drew a line through several paragraphs. After leafing through the rest, he pronounced the reasoning sound. "But unfortunately, the book is based on an error in calculation at the very beginning. As the foundation is faulty, the rest of the edifice is also flawed."
The same happened with the next book. The Rebbe pointed out a sentence that contradicted what the Torah says about a certain juncture of veins. "As our Sages are undoubtedly right, the entire treatise is based on an untruth."
The young man was in a mental turmoil, but eventually had to admit that the mistakes were his. He felt he had no choice but to destroy the books.
The young man began to study with Rabbi Shneur Zalman. Seven weeks later he fell ill, and a short time after that passed away.
Rabbi Shneur Zalmn later revealed that the young man was a reincarnation of Rabbi Eliezer ben Durdia. His soul had already descended into the world several times, each time following the same progression: As a young man it would faithfully observe Torah and mitzvot, but as time passed it invariably left the straight and narrow. "This time, when he came to me, I decided that enough was enough. I refused to let him leave until his soul had accomplished its final tikun (correction)."
(Incidentally, Rabbi Shneur Zalman gave his son, the Mitteler Rebbe, the manuscripts of everything he had learned with the young man. It was based on these writings that he authored his work, Derech Chaim.)
