You are what you read, it has been said. Who were the favorite authors of Saint Thomas Aquinas?
My doctoral dissertation was heavily dependent on St Thomas Aquinas' Prima secundae of the Summa theologiae. Here are the number of citations of authorities found in Secunda pars in the Summa theologiae, which generally examines the purpose of man, vice and virtue, passions, law, grace, and the seven virtues.
Clearly, St. Augustine and Aristotle are the most prevalent - Augustine edged into first place by less than 100 references. Gregory the Great and Dionysius make a happy third and fourth:
Gregory the Great 439
John Damascene 168
Isidore of Seville 120
Roman Law 102
Gregory of Nyssa (actually Nemesius of Ephesus) 41
Prosper of Aquitaine 19
Hilary of Poiteiers 12
These are based on Busa's concordance and lifted from Servais-Theodore Pinkaers, OP "The Sources of the Ethics of St. Thomas Aquinas" in The Ethics of Aquinas, Stephen J. Pope, ed. (Georgetown University Press: Washington DC, 2002), 17.
Happy feast day of Saint Thomas (in the 1962 Calendar)!
Saint Thomas Aquinas, Angelic Doctor, pray for us.