John Henry Newman’s reflections on first principles aim to account for the insurmountable differences between people’s worldviews.1 The emphasis Newman puts on first principles cannot be overstated. Newman argues for the ultimately determinative role that they play in any dispute. There can be little doubt that Newman was familiar with Aristotle’s statement from the Nicomachean Ethics that ‘It is thought. . .that the starting-point or principle is more than half the whole matter.’2 In Newman’s words, these ‘first elements of thought’ are ‘half the battle’.3 Since first principles are so central to the thought of Newman, much has been written on this topic, not only to elucidate Newman’s thoughts on the matter, but also to make sense of the term’s development in Newman’s corpus.4 This article will summarize some of the main points of the latest contributors with special attention to the work of Rik Achten.5 While his work has much to commend for itself, I will criticize one aspect of it while offering a close reading of relevant passages from Aristotle’s Nicomachean Ethics in order to shed light on the noetic aspect of the Illative Sense in its acquisition of first principles.