In this classic work praised by Pope Pius IX himself, Fr. Nicolas J. Laforet lays out the spiritual causes of unbelief, and shows the antidotes necessary to remedy each of those failings.

Noting that unbelief is not a particularly modern phenomenon (after all, many people refused to believe in Jesus even after having witnessed his miracles), Fr. Laforet uncovers the common roots of unbelief as well as the sure remedies that finally bring men and women to have faith in God.

Fr. Laforet shows that although many think otherwise, unbelief is not merely a matter of the intellect; on the contrary, where unbelief prevails we almost invariably find bad will: souls who have either not seriously considered the claims of Christianity or who simply refuse to admit truths that are evident to anyone who inquires with an open mind.