The Department of Philosophy at Trinity College Dublin hosted the 2022 Donnellan Lectures in Philosophy across two evenings, on March 31st and April 1st 2022. The guest speaker was Professor Linda Trinkaus Zagzebski, George Lynn Cross Research Professor emerita and Kingfisher College Chair of the Philosophy of Religion and Ethics emerita at the University of Oklahoma. Her lectures centred on the themes of her book The Two Greatest Ideas: How Our Grasp of the Universe and Our Minds Changed Everything, published by Princeton University Press in 2021. The book examines what Zagzebski argues are the two most transformative ideas in human history: first, that the human mind can comprehend the universe, and second, that the human mind can comprehend itself. She traces how the first idea sparked a remarkable cultural and intellectual awakening during the first millennium BCE, giving rise to philosophy, mathematics, science, and the world's major religions, before the second idea came to dominate from the Renaissance onward. Zagzebski explores how the tension between these two ideas has shaped enduring moral and political debates — from questions of individual autonomy to humanity's relationship with the natural world. The Donnellan Lectures are a prestigious annual series hosted by Trinity's Department of Philosophy, bringing leading international thinkers to campus to engage with students, staff, and the wider public.