A course of lectures given by M.K. Mamardashvili in 1986 — 1987 at Tbilisi University. After lecture courses on Descartes, Kant, Proust, as well as on ancient and modern philosophy, it is the last, final course of the famous philosopher. It is devoted to the topic of thinking taken as an aesthetic phenomenon. Expressive forms, the author assumes, do not exist outside of thought and without discussing the problem of the style and form of thinking itself, its preconditions, which go back to the depths of thought as such, its inexpressibility.