In Conscience, Rosmini brings to their final conclusion the moral principles developed in his earlier Principles of Ethics. Approaching the study from a rational point of view, he also draws upon theology's contribution to clarify and reinforce reason's deliberations on the subject. In this way, he reaches out to believers and non-believers, all of whom, irrespective of their religion or lack of it, inevitably question themselves sooner or later about the good and evil of their own individual actions. The great moral dilemmas of our own day are vividly presented and acutely analysed in a work that clearly foresaw the moral confusion about to fall on our Western civilization. Is conscience the final arbiter of morality? How can false and upright consciences be distinguished? What is to be done in cases of doubtful morality? Can human authority provide help in the formation of conscience? Basing himself on "the system of truth" outlined in the New Essay Concerning the Origin of Ideas, Rosmini sums up his own position in these words: "There is a light in the human being, and a light that is the human being: the light in the human being is… the law of truth; the light that is the human being is an upright conscience… we become light when we share in the law of truth by means of an upright conscience in conformity with truth". How we become that light is the concern of this book.