This episode applies the distinction between personal and shared inquiry—developed in the previous episodes—to philosophical inquiry, arguing that philosophy is a personal affair. It sketches a picture of doing philosophy as the activity of creating an equilibrium of philosophical ideas based on personal nodes that are best described as a kind of intellectual tastes. This picture is shown to be superior to the naturalist picture of philosophy—according to which philosophy is a scientific inquiry—because it can explain why philosophers could rationally believe their theories in the face of systemic peer disagreement and why there can be a sense of philosophical progress in spite of such disagreement.