TMI's teaching is inspired by the Socratic method as well as the Shared Inquiry approach developed by the Great Books Foundation, in which the leader uses primarily open-ended questions to guide discussion.

Instead of conventional lectures, TMI for the most part offers discussion-based seminars that are guided by trained leaders and based upon carefully chosen and sequenced texts representing different perspectives on the questions each group has come together to explore.

[6] The program continues to organize discussion groups on history, literature, science, and other liberal arts topics in residences and meeting places of older adults throughout the Montreal area.

According to Lonergan himself, the 1945 lecture series that he delivered at TMI, entitled "Thought and Reality," served as the seed for his seminal book, Insight: A Study of Human Understanding (1957).

For many years, TMI organized a "Listening to Lonergan" lecture series during the autumn semester, co-sponsored by Concordia University and the Thomas More Research Institute.