Summa Theologica, (Prima Secundae)

Summa Theologica (Prima Secundae) is a book by Thomas Aquinas, first published in the late 13th century. In this section, often called Part I–II, Aquinas treats the foundations of Christian moral theology: human acts, virtues and vices, law, grace, and the principles that govern moral life in relation to our ultimate end.

He builds upon his earlier Prima Pars (dealing with God and creation) and anticipates later sections on virtue and Christ. Thomas Aquinas, a medieval Dominican theologian and philosopher, sought to unite Christian doctrine with Aristotelian philosophy. His Summa Theologica became a central work in scholastic theology and Christian philosophy, shaping the tradition known as Thomism.

The Prima Secundae offers a rigorous moral framework, exploring what it means for human beings to act well, how virtues and passions play a role, and how natural law and divine grace guide moral responsibility.

This text remains influential in Catholic theology, philosophy of ethics, and the dialogue between faith and reason, and has deeply impacted Western intellectual history.

This translation by Laurence Shapcote (the Fathers of the English Dominican Province) was first published in 1911.