Father William Slattery, Ph.D., S.T.L., was born in Dungarvan, county Waterford, in southern Ireland, in 1961. His birthplace was close to two of the ancient Celtic monasteries in Ardmore and Lismore, centers from which the Irish monks embarked to convert mainland Europe to the Faith of Our Lord Jesus Christ. He used also to cycle to the present-day abbey of Mount Melleray, located on the slopes of the Knockmealdown Mountains, a place where the faith of the Trappist monks inspires one with the fundamental truth that our lives are made to be God-centered.
He did his high school education in the Augustinian order’s St. Augustine’s College in Abbeyside. Then, at 17 years of age, he began his studies for the priesthood by entering the Legionaries of Christ. He studied in Dublin, the Spanish city of Salamanca, and in Rome at the Gregorian University where he obtained a Ph. L. before being ordained to the priesthood in St. Peter’s Basilica by Saint John Paul II on the Feast of the Holy Name of Jesus, 1991.
From 1991 to 1999 he was based near New York City and worked throughout the north-eastern United States, raising funds for vocations to the priesthood and preaching the Spiritual Exercises of St. Ignatius. From 1999 to 2005 he worked to foster vocations from Quebec and Ontario in Canada through preaching retreats, giving spiritual direction, and directing groups of students at university and high school levels studying Catholic apologetics (Faith and reason).
In 2005 he decided to begin the process of transferring from the Legionaries of Christ by going to the Diocese of Peterborough. Bishop Nichola de Angelis, in 2006, sponsored him to study in Rome where he resided at the Casa Santa Maria, the graduate house of the Pontifical North American College. He obtained firstly a licenciate in theology ( S. T. L.), specializing in fundamental theology at the Pontifical Lateran University, writing a minor thesis entitled An Inquiry into Theological Method in the Systematic Works of Saint Thomas Aquinas. He then graduated with a PhD in philosophy from the Pontifical Gregorian University, writing a thesis in the area of epistemology that analyzed a modern theory of alethic logic in the light of the metaphysical theory of cognition of St. Thomas Aquinas: A Critical Study of Antonio Livi’s Alethic Logic in the light of the Epistemology of St. Thomas Aquinas and in the historical context of the semantics and concepts for “common sense”.
While in Rome he wrote much of the work Heroism and Genius: How Catholic Priests Built Western Civilization, a history of the role of the Catholic priesthood in laying the socio-political and cultural foundations of the ethos and chief institutions that sealed Western culture until modern times as original and originating in Catholicism.
He also drafted a series of books on the formation of priests – intellectual, ascetical-mystical, and pastoral – according to the ancient wisdom of the Church’s Tradition and in the light of the challenges of the secularized culture of the Third Millennium (to be used in the formation of Ignatians).
In 2016 Leonardo da Vinci publishing house published his work The Logic of Truth.
In 2017 Ignatius Press published Heroism and Genius: How Catholic Priests Helped to Build – and can Help Rebuild – Western Civilization.
In these years he has also written another book entitled The Secret of the Ancient Rite: How the Traditional Mass Inspirited Genius and Heroism to Christendom, which, Deo volente, will be published in the future.
He speaks English, French, Spanish and Italian and has studied Gaelic, Latin, Greek and German.