Complex sentence: In addition to his classical and mathematical knowledge he was a master of scholastic theology and was the author of a much-quoted inspirational letter, A Letter to the Most Illustrious the Contessina Allagia degli Aldobrandeschi, Written Christmas Eve Anno Domini 1513.
Split into simpler sentences: In addition to his classical and mathematical knowledge he was a master of scholastic theology. He was also the author of a much-quoted inspirational letter, A Letter to the Most Illustrious the Contessina Allagia degli Aldobrandeschi, Written Christmas Eve Anno Domini 1513.