Double-Effect Reasoning

Abstract

Consequentialists oppose while absolutists and deontologists rely upon double-effect reasoning (DER) to address hard cases in which good inextricably binds with evil (such as destroying a legitimate military target while concomitantly and foreseeably killing innocents). This book addresses the history, application, and philosophical controversy concerning DER. It traces both the origin of DER in the thought of Aquinas and its development by subsequent ethicists. Considering consequentialist criticisms, proportionalism, and recent revisions of double effect, the book argues at length for the reasonableness of DER, particularly the intended/foreseen distinction. Intent is distinguished from foresight, and this distinction is applied to the classic cases of terror and tactical bombing. Most importantly, the book establishes the ethical relevance of this distinction, grounding its import both in broadly Aristotelian-Thomistic features of action as voluntary, and in a Kantian focus on the victim as an end in himself. The book also considers typically neglected albeit intriguing issues such as DER’s application to allowings and how constitutional legal systems that incorporate exceptionless norms employ a legal analogue to DER.