Looking for truth? Meet your new guide, St. Thomas Aquinas.

St. Thomas Aquinas (1225-1274) is widely regarded as one of the world's greatest philosophers and theologians. A masterful interpreter of reality, he has proven to be one of history’s finest teachers. His writings assist us in answering perennial questions about God, man, the natural world, law, and morality, as well as questions of special relevance to our time, like the relationship between modern science and faith or pursuing happiness in the digital era.

For centuries, St. Thomas’s philosophical and theological teachings have helped countless men and women like you pursue truth, deepen their faith, and develop a holistic understanding of the human person. Learning from St. Thomas won’t just help you understand yourself and the world around you — it will make you a better spouse, parent, friend, community member, and evangelist.

What Is Aquinas 101?

Aquinas 101 is a project of the Thomistic Institute that seeks to promote Catholic truth and the thought of St. Thomas Aquinas. While the writings of St. Thomas may seem daunting at first, Aquinas 101 simplifies the learning process through short, engaging videos, making it enjoyable and accessible.

Each Aquinas 101 video walks you through a different theme in just a few minutes — no preparation required. If you’d like to dive deeper, you can enroll in a course, explore accompanying readings and lectures, or dive into St. Thomas’s words yourself in our digital Summa Theologiae!

Trusted Guides

Our team of Dominican friars will lead you step-by-step to shed light on complex topics

Real Answers

Learn about the nature of man, God, happiness, and Jesus Christ's presence in the world today

About the Thomistic Institute

The Thomistic Institute is a research institute of the Pontifical Faculty of the Immaculate Conception at the Dominican House of Studies in Washington, D.C. Promoting Catholic truth in the contemporary university is the primary focus of our work. We accomplish this through our campus chapters program, academic conferences, intellectual retreats, and other initiatives.

In addition to our work on campus, we also promote the Catholic intellectual tradition online. Initially created to serve the students in our campus programs, Aquinas 101 now enjoys a global audience of all ages. We also regularly post recordings of academic lectures we organize on our popular Thomistic Institute Podcast.

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Our mission

The Thomistic Institute exists to promote Catholic truth in our contemporary world by strengthening the intellectual formation of Christians at universities, in the Church, and in the wider public square. The thought of St. Thomas Aquinas, the Universal Doctor of the Church, is our touchstone.

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How to Think Like a Thomist: An Introduction to Thomistic Principles

Everyone needs some introduction to the basic vocabulary and concepts that St. Thomas Aquinas uses in his philosophical and theological works. These lessons will give you a basic confidence to navigate St. Thomas’s way of thinking and teaching. Terms like “act and potency,” “form and matter,” “efficient and final cause,” will become clearer, and prepare you to follow Aquinas on his many paths to the one Truth.

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Jesus Christ, the Savior of the World

Christ is man’s way back to God, through His Incarnation, all the deeds and sufferings of His life, and the sacraments that He instituted to give us a share in that life. In this course, we will explore the beginning of the third section of the Summa Theologiae, which charts out who Christ is and our life in Him, according to St. Thomas Aquinas.

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Introduction to St. Thomas Aquinas

Who is St. Thomas, and what sets him apart from every other intellectual guide? This course aims to introduce the viewer to this exemplary scholar-saint and to shed light on the reasons for his enduring legacy and importance in the great Catholic Intellectual Tradition. This course will help you navigate his works, and join Aquinas in pursuit of Truth.

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Meet Our Speakers

Fr. Thomas Davenport, O.P.

Professor of Philosophy, Angelicum.

About

Fr. Thomas Davenport, O.P. is an American Dominican, physicist, and philosopher. Before joining the Dominican Order, he studied physics at the California Institute of Technology and earned his doctorate in physics from Stanford University studying theoretical particle physics. He was ordained a priest in 2017 and holds a Licentiate in Philosophy from the Catholic University of America, focusing on the philosophy of science and natural philosophy. In 2020, he joined the faculty of philosophy at the Pontifical University of St. Thomas Aquinas in Rome while working on his second Ph.D. – this time, in philosophy. He is a frequent speaker on the intersection of faith and science and serves on the Board of Directors of the Society of Catholic Scientists.

Fr. Ambrose Little, O.P.

Assistant Director, Thomistic Institute. Instructor in Philosophy, Dominican House of Studies.

About

Fr. Ambrose Little is an Assistant Director of the Thomistic Institute and an Assistant Professor of Philosophy at the Pontifical Faculty of the Immaculate Conception. Originally from Connecticut, he entered the Dominican Order in 2007 and was ordained a priest in 2013. He completed his doctorate in Philosophy at the University of Virginia and holds both a B.A. and a Licentiate in Philosophy from The Catholic University of America.

Fr. John Baptist Ku, O.P.

Associate Professor of Dogmatic Theology, Dominican House of Studies

About

Fr. John Baptist Ku was born in Manhattan and grew up in Fairfax, Virginia. After graduating from the University of Virginia, he worked at AT&T for five years before entering the Dominican Order in 1992. He served for three years in St. Pius V Parish in Providence, Rhode Island, and completed his doctoral studies in dogmatic theology at the University of Fribourg in Switzerland. He began teaching for the Pontifical Faculty of the Immaculate Conception in 2008.

Fr. Aquinas Guilbeau, O.P.

Assistant Professor of Moral Theology, Dominican House of Studies. University Chaplain, The Catholic University of America.

About

A native of Louisiana, Fr. Aquinas Guilbeau, O.P., entered the Dominican Province of St. Joseph in 2005. After several years of pastoral work in New York City, Fr. Guilbeau began doctoral studies in moral theology at the University of Fribourg, where he completed a dissertation on St. Thomas Aquinas’s doctrine of the common good. He is currently the University Chaplain and Director of Campus Ministry at the Catholic University of America.

Fr. Gregory Pine, O.P.

Assistant Director of Campus Outreach, Thomistic Institute. Adjunct Professor, Dominican House of Studies.

About

Fr. Gregory Pine, O.P. is an adjunct professor of dogmatic theology at the Dominican House of Studies and an Assistant Director of the Thomistic Institute. He was ordained a priest in 2016 and holds an STL from the Dominican House of Studies. He is the co-author of Credo: An RCIA Program and Marian Consecration with Aquinas as well as the author of Prudence: Choose Confidently, Live Boldly. His writing also appears in Ascension’s Catholic Classics series, Magnificat, and Aleteia. He is a regular contributor to the podcasts Pints with Aquinas, Catholic Classics, The Thomistic Institute, and Godsplaining.

Fr. Andrew Hofer, O.P.

Associate Professor of Patristics and Ancient Languages and Director of the Doctoral Program, Dominican House of Studies

About

Fr. Andrew Hofer, O.P. grew up as the youngest of ten children on a Kansas farm. He is a Dominican priest of the U.S. Eastern Province of St. Joseph and the author of Christ in the Life and Teaching of Gregory of Nazianzus (Oxford University Press, 2013) and The Power of Patristic Preaching: The Word in Our Flesh (The Catholic University of America Press, 2023) as well as co-author of A Living Sacrifice: Guidance for Men Discerning Religious Life (Vianney Vocations, 2019). He is editor of the speculative quarterly The Thomist and editor or co-editor of several volumes on patristic theology, deification, and St. Thomas Aquinas.

Fr. Cajetan Cuddy, O.P.

Instructor in Dogmatic and Moral Theology, Dominican House of Studies

About

Fr. Cajetan Cuddy, O.P., is a priest of the Dominican Province of St. Joseph. He received his doctorate in Sacred Theology from the University of Fribourg, Switzerland. He serves as the general editor of the Thomist Tradition Series, and he is co-author of Thomas and the Thomists: The Achievement of St. Thomas Aquinas and His Interpreters. He has written for numerous publications on the philosophy and theology of St. Thomas Aquinas and the Thomist Tradition.

Fr. Thomas Petri, O.P.

President and Assistant Professor of Moral Theology and Pastoral Studies, Dominican House of Studies

About

Fr. Thomas Petri, O.P. is the President and Assistant Professor of Moral Theology and Pastoral Studies at the Pontifical Faculty of the Immaculate Conception, where he formerly served as Vice President and Dean. Fr. Petri entered the Dominican Order in 2004 and was ordained a priest in 2009. He earned his S.T.L. from the Pontifical Faculty of the Immaculate Conception and his Doctorate in Sacred Theology from The Catholic University of America. Fr. Petri is a member of the Academy of Catholic Theology. He is the author of Aquinas and the Theology of the Body: The Thomistic Foundations of John Paul II’s Anthropology (CUA Press, 2016).

Fr. John Mark Solitario, O.P.

Coordinator for Campus Outreach, Thomistic Institute

About

Fr. John Mark is a coordinator for campus outreach at the Thomistic Institute. He met the nuns and friars of the Order of Preachers at the Dominican Monastery of the Mother of God in his hometown of West Springfield, MA. Their lives of Christian totality, marked by sacrifice, prayer, and preaching but above all, a supernatural goodness and joy, made a huge impact on him. After studying the liberal arts and philosophy at Christendom College and teaching high school theology as a member of Providence College’s PACT program, Father entered the Dominican novitiate in Cincinnati, OH, and went on for theological studies at the Dominican House of Studies. He was ordained a priest in 2019 and earned his licentiate in sacred theology in 2020.

Prof. Karin Öberg, Ph.D.

Professor of Astronomy and the Thomas Dudley Cabot Professor of Natural Sciences, Harvard University

About

Karin Öberg is Professor of Astronomy at Harvard University. Her research aims to uncover how chemical processes affect the outcome of planet formation, especially the chemical habitability of nascent planets. She obtained her B.Sc. in chemistry from Caltech in 2005 and her Ph.D. in astronomy from Leiden University in 2009. She did postdoctoral work at Harvard-Smithsonian Center for Astrophysics as a NASA Hubble fellow, joined the Harvard astronomy faculty in 2013, and was promoted to full professor with tenure in 2017. Her research in astrochemistry has been recognized with a Sloan fellowship, a Packard fellowship, the Newton Lacy Pierce Award from the American Astronomical Society, a Simons investigator award, and the Max Planck Society Harnack lecture. She serves on the boards of the Society of Catholic Scientists and the Angelicum.

Fr. Thomas Joseph White, O.P.

Rector Magnificus, Pontifical University of St. Thomas (Angelicum)

About

Fr. Thomas Joseph White is the Rector Magnificus of the Pontifical University of St. Thomas (Angelicum) in Rome. He is the author of various books and articles including Wisdom in the Face of Modernity: A Study in Thomistic Natural Theology (Sapientia Press, 2011), The Incarnate Lord, A Thomistic Study in Christology (The Catholic University of America Press, 2015) Exodus (Brazos Press, 2016), The Light of Christ: An Introduction to Catholicism (The Catholic University Press, 2017), The Trinity: On the Nature and Mystery of the One God (The Catholic University Press, 2022), and Principles of Catholic Theology, Book 1 (The Catholic University of America Press, 2023). He is co-editor of the journal Nova et Vetera, a Distinguished Scholar of the McDonald Agape Foundation, and a member of the Pontifical Academy of St. Thomas Aquinas.

Fr. Jonah Mary Teller, O.P.

Parochial Vicar at St. Joseph's Church in Greenwich Village

About

Fr. Jonah Teller was a Coordinator for Campus Outreach at the Thomistic Institute and is currently the parochial vicar at St. Joseph's Church in Greenwich Village. He holds an STL from the Pontifical Faculty of the Immaculate Conception at the Dominican House of Studies. He did his undergraduate studies at the University of Dallas. He has contributed to work published in Nova et Vetera and, along with Fr. Andrew Hofer, O.P., he is the co-composer of Nine Days with St. Joseph and Nine Days with St. Michael, published by Magnificat. He is also a member of The Hillbilly Thomists.

Prof. Jonathan I. Lunine, Ph.D.

David C. Duncan Professor in the Physical Sciences and Chair, Department of Astronomy, Cornell University

About

Jonathan I. Lunine is David C. Duncan Professor in the Physical Sciences of Cornell University and Chair of the Department of Astronomy (Ph.D. Planetary Science 1985, Caltech). From January through May 2023 he was the McDonald Agape Visiting Scholar at the Dominican House of Studies. Prof. Lunine does research in astrophysics, planetary science and astrobiology. He is a member of the U.S. National Academy of Sciences, and among other awards is the recipient of the Jean Dominique Cassini Medal of the European Geosciences Union (2015) and the Basic Sciences Award of the Int. Academy of Astronautics (2009). He is the author of Astrobiology, A Multidisciplinary Approach (Pearson Addison-Wesley, 2005) and Earth: Evolution of a Habitable World (2nded., Cambridge Univ. Press, 2013).

Fr. Irenaeus Dunlevy, O.P.

Coordinator for Campus Outreach, Thomistic Institute

About

Fr. Irenaeus Dunlevy, OP is a Coordinator for Campus Outreach at the Thomistic Institute. He received his S.T.L. from the Pontifical Faculty of the Immaculate Conception in 2021, writing his tesina, "Divine Architect: firmitas, utilitas, claritas." He also holds a M.Arch from Virginia Tech, earning the Director's Award for his thesis, "On Ornament: A Catholic Cemetery for Philadelphia." Prior to entering the Order of Preachers in 2013, he practiced for several years at a religious architecture firm. Ordained a priest in 2020, he has served as a parochial vicar, assistant college chaplain, and taught at Providence College, where he created the courses Dominican Intellectual Tradition and Architecture and the Sacred.

Fr. James Brent, O.P.

Assistant Professor of Philosophy, Dominican House of Studies

About

Fr. James Dominic Brent, O.P. was born and raised in Michigan. He completed his doctorate in Philosophy at Saint Louis University on the epistemic status of Christian beliefs according to Saint Thomas Aquinas, and has articles on natural theology, on God’s knowledge and will, and on the epistemology of theology in Thomas Aquinas. He has a Licentiate in Sacred Theology, taught in the School of Philosophy at The Catholic University of America, and now teaches philosophy at the Dominican House of Studies in Washington, DC. He is the author of The Father's House: Discovering Our Home in the Trinity (December 2023 from Pauline Books and Media).

Fr. Dominic Langevin, O.P.

Vice President, Academic Dean, Assistant Professor of Dogmatic Theology, Dominican House of Studies

About

Fr. Dominic Langevin, O.P., is dean and assistant professor of dogmatic theology at the Dominican House of Studies, where he teaches courses principally in sacramental theology and liturgiology. He is the secretary/treasurer of the Academy of Catholic Theology. He did his undergraduate degree at Yale University. He entered the Dominican Order in 1998 and was ordained a priest in 2005. He earned his doctorate from the University of Fribourg while working as the assistant to the chair of dogmatic theology for ecclesiology and the sacraments. He is the author of From Passion to Paschal Mystery and was editor of the journal The Thomist from 2018 to 2021.

Fr. Dominic Legge, O.P.

Director, Thomistic Institute. Associate Professor of Dogmatic Theology, Dominican House of Studies.

About

Fr. Dominic Legge is the Director of the Thomistic Institute and Associate Professor in Systematic Theology at the Pontifical Faculty of the Immaculate Conception in Washington, D.C. He holds a J.D. from Yale Law School, a Ph.L. from the School of Philosophy of the Catholic University of America, and a doctorate in Sacred Theology from the University of Fribourg in Switzerland. He entered the Order of Preachers in 2001, after having practiced constitutional law for several years as a trial attorney for the U.S. Department of Justice. He has also taught at The Catholic University of America Law School and at Providence College. He is the author of The Trinitarian Christology of St. Thomas Aquinas (Oxford University Press, 2016).

Fr. Jordan Schmidt, O.P.

Assistant Professor of Sacred Scripture, Dominican House of Studies

About

Fr. Jordan Schmidt was born in Fargo, ND, and attended St. John’s University in Collegeville, MN for his undergraduate studies. After entering the Order of Preachers, he came to Washington DC to study theology, graduating from the PFIC in 2009 with an STB/MDiv in theology, and from CUA in 2012 with an STL in biblical theology. Upon his ordination to the priesthood, he was appointed associate pastor of St Mary’s parish in New Haven, CT where he served until 2013. Fr. Jordan next returned to the Dominican House of Studies in Washington, DC to pursue doctoral studies at CUA. Since earning his PhD in biblical studies in 2018, he has been teaching various courses in Sacred Scripture at the PFIC.

Fr. Philip-Neri Reese, O.P.

Associate Professor of Philosophy, Angelicum

About

Fr. Philip-Neri Reese, O.P., is a Dominican friar of the Province of St. Joseph and an Associate Professor of Philosophy at the Pontifical University of St. Thomas (Angelicum) in Rome. He is also the director of the Angelicum Thomistic Institute's new Project on Philosophy and the Thomistic Tradition. He received his Licentiate in Philosophy from the Catholic University of America and his Doctorate in Philosophy from the University of Notre Dame. His main areas of research are metaphysics, its history, and its methodology, with a special emphasis on the thought of St. Thomas Aquinas and its subsequent reception, but he has also published articles on Christology, philosophical anthropology, ethics, and scholastic economics.

See what people are saying

“The Aquinas 101 videos are great for drawing a wide range of people together because they introduce difficult concepts in philosophy and theology clearly and simply such that everyone can begin to understand… They strike a good blend of intellectual depth with simple examples, and the animations and the personality of the speakers often inject both lighthearted fun and clarity into the presentation.”Zachary HuberGraduate Student & TI Chapter President · Cornell University