On Evil

On Evil

On Evil

On Evil


The De Malo represents some of Aquinas' most mature thinking on goodness, badness, and human agency. In it he examines the full range of questions associated with evil: its origin, its nature, its relation to good, and its compatibility with the existence of an omnipotent, benevolent God. This edition offers Richard Regan's new, clear readable English translation, based on the Leonine Commission's authoritative edition of the Latin text. Brian Davies has provided an extensive introduction and notes. (Please note: this edition does not include the Latin text).


Is anything objectively evil? Is anything objectively good? How does what is evil differ from what is good? Can there be evil without good? Does evil have a cause? Does goodness have a cause? Do people have freedom of choice? Or is what they do always outside their control? If people can act freely, under what conditions can they be rightly thought to be responsible for what they do? And how is their behavior to be evaluated and explained? Is there such a thing as sin? If so, what is it? And how does it arise? Does it admit of degrees? Does it come from what is not human? Or does its source lie wholly in us?

These are questions that Aquinas discussed at various times in his life. But he was especially concerned with them when completing his Disputed Question De malo (On Evil). Probably prepared for publication in the early to mid–1270s, this work represents some of Aquinas's most mature thinking on goodness, badness, and human agency. Together with the Second Part of the Summa theologiae, it is one of his most sustained contributions to moral philosophy and theology and ranks among his major writings.

In the present work readers will find a new translation of the De malo based on the authoritative 1982 edition provided by the Leonine Commission. They will also find a detailed introduction designed to place the De malo in the context of Aquinas's life and thought. At the end of the work there are notes on certain terms used in the De Malo, notes on auhtors cited in it, and a list of texts referred to by Aquinas.

Some years ago I suggested to Father Vincent Potter S. J. that there was need for a new English edition of the De malo. Even though he was suffering from severe medical disabilities, Father Potter managed to complete a first-draft translation of the text just before he died in 1994. This draft, however, was very much a preliminary one. Richard Regan S. J. subsequently agreed to translate the De malo afresh, and it is his translation that appears below.

In my editorial work for this volume I owe a huge debt to Sara Penella. She has assisted me in all sort of ways, especially in the compilation of notes on authors and texts referred to in the De malo.

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