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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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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The Sacraments and Salvation

The seven sacraments of the Church are extensions of Christ’s presence in the world. He gave them to us so that we can encounter him at every point in our lives. But what are the sacraments really? Where did they come from? How do they work? And why do we need them? There are answers to these questions, and learning them can change your life. Guided by St. Thomas, we’ll explore the Church’s sacramental riches in this course so that you can better experience their transforming power in your life.

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Meet Our Speakers

Fr. Ambrose Little, O.P.

Assistant Director, Thomistic Institute. Assistant Professor of Philosophy, Dominican House of Studies.

About

Fr. Ambrose Little, O.P. 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. Andrew Hofer, O.P.

Ordinary 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. Aquinas Guilbeau, O.P.

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

About

Fr. Aquinas Guilbeau, O.P. is a Visiting Assistant Professor of Moral Theology at the Pontifical Faculty of the Immaculate Conception. A native of Louisiana, he 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. Cajetan Cuddy, O.P.

Assistant Professor of 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. Dominic Langevin, O.P.

Vice President, Academic Dean, and 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 Pontifical Faculty of the Immaculate Conception, 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, O.P. is the Director of the Thomistic Institute and Associate Professor in Systematic Theology at the Pontifical Faculty of the Immaculate Conception in Washington, DC. 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. Gregory Pine, O.P.

Assistant Director of Campus Outreach, Thomistic Institute. Instructor of Dogmatic and Moral Theology, Dominican House of Studies.

About

Fr. Gregory Pine, O.P. is an Assistant Director of the Thomistic Institute and an Instructor of Dogmatic and Moral Theology at the Pontifical Faculty of the Immaculate Conception. He was ordained a priest in 2016 and holds a doctorate from the University of Fribourg (Switzerland). 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. He is a regular contributor to the podcasts Pints with Aquinas, The Thomistic Institute, and Godsplaining.

Fr. Irenaeus Dunlevy, O.P.

Coordinator for Campus Outreach, Thomistic Institute.

About

Fr. Irenaeus Dunlevy, O.P. 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 and Chaplain to Commuter Students, Dominican House of Studies.

About

Fr. James Dominic Brent, O.P. is a Dominican friar of the Province of St. Joseph. Born and raised in Michigan, he earned his doctorate in Philosophy from St. Louis University on the epistemic status of Christian beliefs according to Saint Thomas Aquinas. He has articles in the Internet Encyclopedia of Philosophy on “Natural Theology,” in the Oxford Handbook of Thomas Aquinas on “God’s Knowledge and Will”, and in the Oxford Handbook of the Epistemology of Theology on “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 Pontifical Faculty of the Immaculate Conception. He is the author of The Father's House: Discovering Our Home in the Trinity (December 2023 from Pauline Books and Media), frequently gives lectures for the Thomistic Institute, and is the host of Contemplata, a podcast for contemplative souls.

Fr. John Baptist Ku, O.P.

Associate Professor of Dogmatic Theology, Dominican House of Studies.

About

Fr. John Baptist Ku, O.P. 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. John Mark Solitario, O.P.

Coordinator for Campus Outreach, Thomistic Institute.

About

Fr. John Mark Solitario, O.P. 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 Pontifical Faculty of the Immaculate Conception. He was ordained a priest in 2019 and earned his licentiate in sacred theology in 2020.

Fr. Jonah Mary Teller, O.P.

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

About

Fr. Jonah Teller, O.P. was a Coordinator for Campus Outreach at the Thomistic Institute and is now the Parochial Vicar at St. Joseph's Church in Greenwich Village, NY. 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.

Fr. Jordan Schmidt, O.P.

Assistant Professor of Sacred Scripture and Director of Pastoral Field Education, Dominican House of Studies.

About

Fr. Jordan Schmidt, O.P. 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 Pontifical Faculty of the Immaculate Conception in 2009 with an STB/MDiv in theology, and from the Catholic University of America 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 the Catholic University of America. Since earning his Ph.D. in biblical studies in 2018, he has been teaching various courses in Sacred Scripture at the Pontifical Faculty of the Immaculate Conception.

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.

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. 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. Thomas Joseph White, O.P.

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

About

Fr. Thomas Joseph White, O.P. 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.

Prof. Jonathan I. Lunine, Ph.D.

David C. Duncan Professor in the Physical Sciences and Chair, Department of Astronomy, Cornell University. McDonald Agape Visiting Scholar, Dominican House of Studies.

About

Dr. 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 (2nd ed., Cambridge Univ. Press, 2013).

Prof. Karin Öberg, Ph.D.

Professor of Astronomy and the Thomas Dudley Cabot Professor of Natural Sciences, Harvard University. McDonald Agape Visiting Scholar, Dominican House of Studies.

About

Dr. 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. From January through May 2024, she was the McDonald Agape Visiting Scholar at the Dominican House of Studies.

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