Immanuel Kant’s Critique of Pure Reason is a core text of modern philosophy. Presenting an examination of the nature of human reason, its central argument is that the way in which man perceives his environment is a direct consequence of the mind’s ability to act on this environment and convert it into something meaningful. The work brings together two opposing schools of philosophy—rationalism and empiricism—and proposes a third way, which came to be known as transcendental idealism. The work proved to be hugely influential, not least on Marx, Heidegger and Nietzsche.

Composed in four parts between 1883 and 1885, Thus Spoke Zarathustra is the most famous and influential work of German philosopher Friedrich Nietzsche. The work is a philosophical novel in which the character of Zarathustra, a religious prophet-like figure, delivers a series of lessons and sermons in a Biblical style that articulate the central ideas of Nietzsche's mature thought.

After more than 2,300 years, the Greek philosopher Aristotle still remains one of the most influential thinkers who has ever lived. There was hardly any field of human knowledge in existence during his day in which he did not make a major contribution. Additionally, he probed areas which were never before examined. Indeed, one could make the claim that no individual person has ever known as much about this world as Aristotle. His analyses of zoology and logic paved the way for modern forensic techniques, and for which every scientist down to this day owes him a debt of gratitude.

The State and Revolution (1917) is a well-known book by Vladimir Lenin. In the book, Lenin describes the role of the state in society, the necessity of proletarian revolution, and the theoretic inadequacies of social democracy in achieving revolution to establish the dictatorship of the proletariat.

This metaphysical self-help classic instills happiness within and urges individuals to pursue a content life without sin, boredom, or contempt. Written decades ago with post-war depression in mind, this text has transcended time and continues to give applicable advice for modern-day individuals.