Medieval philosophy
Arguably Versfeld's most systematic books are "The perennial order" (1954) and "The mirror of philosophers" (1962). One finds in these books his engagement with Medieval philosophy – particularly Augustine and Aquinas – as well as with modern and contemporary philosophers. His work is characterised by the quest for an ethic of humaneness and care for the environment. This ethic is developed from intensive studies in philosophical anthropology. In the horizon of his work remains his opposition to the unjust political dispensation in South Africa.