What is the author's tone in The Memory Palace of Matteo Ricci by Jonathan D. Spence?

The tone of The Memory Palace is much like the perspective; since the author is a distinguished historian with no obvious bias or axe to grind, the tone of the book is erudite, detailed, measured, nuanced, and thoroughout maintaining a clear, compelling narrative. The author seeks to give a detailed story of the history of Matteo Ricci's mission work in China and his life prior to this, along with outlining the cultural, historical and theological features of the late 15th and early 16th centuries in both Europe (particularly Italy) and China.