P. Byrne 
Philosophical and Ethical Problems in Mental Handicap [PDF ebook] 

This book examines a range of important conceptual, ethical, social and religious issues arising from mental handicap. It contains a vigorous defence of the contention that mentally handicapped human beings are persons. It attacks both the contemporary philosophical attempts to dismiss the personhood of mentally handicapped people and the genocidal policies which those attempts suggest. It explores the logic of the attitudes which have lead to the marginalisation and oppression of the mentally handicapped.