In 1469 Paolo wrote on his tax assessment that he was too old to work any more and that his wife was ill. Giorgio Vasari, who, 100 years later, researched and wrote the lives of many painters, wrote that, unfortunately Paolo was badly offended by Donatello, who looked at his latest painting and told him, for a joke, to cover it up. Vasari said that Paolo was so hurt that refused to come out of his room but sat working at his drawings, and whenever his wife called him to come to bed he would answer "What a wonderful thing perspective is!"