He was a member of the Princeton faculty since 1967, teaching in both the History Department and in Humanistic Studies, an interdisciplinary program. He also directed Princeton's Community College programs.
In 1970, the same year he received a Guggenheim Fellowship, he co-founded the Journal of Interdisciplinary History with Robert I. Rotberg. He was also an advisor for the 1993 television series Renaissance. He was a member of the board of editors of the journals Computers and the Humanities, Computer Studies in the Humanities and Verbal Behavior, and Climatic Change.
Emergence of International Business 1200-1800, Volume III: Enterprise and Empire (New York: Taylor & Francis, 1999)
The Last Days of the Renaissance & the March to Modernity (New York: Basic Books, 2006)
Why Does Michelangelo Matter?: A Historian's Questions about the Visual Arts (Palo Alto, California: The Society for the Promotion of Science and Scholarship, 2018). A collection of reviews of art history books and art exhibitions.
'On Nominalism and Idealism, Historical and Statistical: A Response to Roger Schofield', The Historical Journal, 15 (1972): 788–793
'The Expansion of Europe and the Spirit of Capitalism', The Historical Journal, 17 (1974): 675–689
'Court Festivals of the European Renaissance: Art, Politics and Performance', English Historical Review, 118 (2003): 1384–1385
'Observations - Why Michelangelo Matters: His Spiritual World has Vanished, But the Master's Quest for Perfection is Rightly Irresistible', Commentary, 122 (2006): 56
'Those Who Do Not Learn History...', Chronicle of Higher Education, 53 (2007)