The book clearly explains the shift to modern philosophy from the realism of Aristotle to the Idealism of Descartes and how Idealism led to the irrationalism that dominates our time. In the book A Companion to Reading Newman's Grammar of Assent, the author explains Newman's truths by illustrating them as they pertain to contemporary Catholic issues. Through his personal notes, he provides delightful windows into his own soul with its struggles from childhood faith, to confusion, to militant buoyant faith. If you struggle with doubt this is the book for you. If you are a 100% believer, it will be great to use with doubters you know. Their name is legion.