The document discusses Albrecht Dürer's magic square from 1514. The magic square is a 4x4 grid of numbers with the property that the sums of each row, column, and diagonal all equal 34. Dürer arranged the numbers such that this magic sum of 34 would be preserved no matter how the squares were rotated or which quarters were summed. The magic square is believed to have numerical and symbolic meanings for Dürer related to numerology and the year his mother died.