Philosophical Investigations was published in 1953, two years after the death of its author. In the preface written in Cambridge in 1945 where he was professor of philosophy he states: ‘Four years ago I had occasion to re-read my first book (the Tractatus Logico-Philosophicus) and to explain its ideas to someone. It suddenly seemed to me that I should publish those old thoughts and the new ones together: that the latter could be seen in the right light only by contrast with and against the background of my old way of thinking.’

Being and Time was published in 1927 during the Weimar period in Germany, a time of political, social and economic turmoil. Heidegger himself did not escape the pressures and his nationalism, and undeniable anti-Semitism in the following decades cast a shadow over the man, but not the work. Being and Time is not coloured by expressions of his later views (unlike other writings) and remains an outstanding document.  

As philosophy professor Taylor Carman explains in his helpful introduction, Edmund Husserl (1859-1938) was the founder of modern phenomenology, one of the most important and influential movements of the 20th century. Ideas, published in 1913 – its full title is Ideas for a Pure Phenomenology and Phenomenological Philosophy – was the key work. It is arguably ‘the most fundamental and comprehensive statement of the fundamental principles of Husserl’s mature philosophy’. 

 The year is 1919. The horror of the First World War is fresh for the protagonists of Time of the Magicians, each of whom finds himself at a crucial juncture. Benjamin is trying to flee his overbearing father and floundering in his academic career, living hand to mouth as a critic. Wittgenstein, by contrast, has dramatically decided to divest himself of the monumental fortune he stands to inherit, in search of spiritual clarity.

Born in Vienna into an extremely wealthy and highly cultured family, Ludwig Wittgenstein (1889-1951) grew up surrounded by art, music, and a disturbing amount of dysfunctional behavior. After studying mechanical engineering and developing an interest in aeronautics, he became obsessed with mathematics and logic, which led to his life's work exploring the relationship between language, philosophy, and reality.

The Problems of Philosophy discusses Bertrand Russell's views on philosophy and the problems that arise in the field. Russell's views focus on knowledge rather than the metaphysical realm of philosophy. The Problems with Philosophy revolves around the central question that Russell asks in his opening line of Chapter 1 - Is there any knowledge in the world which is so certain that no reasonable man could doubt it?

Published in 1797, the Critique of Pure Reason is considered to be one of the foremost philosophical works ever written. In the Critique of Pure Reason, Immanuel Kant explores the foundation of human knowledge and its limits, as well as man's ability to engage in metaphysics.

From the perspective of an unbeliever, Fear and Trembling explores the paradox of faith, the nature of Christianity, and the complexity of human emotion. Kierkegaard examines the biblical story of Abraham, who was instructed to sacrifice his son Isaac, and forces us to consider Abraham's state of mind. What drove Abraham, and what made him carry out such an absurd and extreme request from God? Kierkegaard argues that Abraham's agreement to sacrifice Isaac, and his suspension of reason, elevated him to the highest level of faith. 

Slavoj Žižek's first book is a provocative and original work looking at the question of human agency in a postmodern world. In a thrilling tour de force that made his name, he explores the ideological fantasies of wholeness and exclusion which make up human society. 

Aion is one of the major works of C.G. Jung's later years. The title comes from the Greek word for aeon or age and refers to the age of Christianity, for, in Aion, Jung is concerned with the collective psychic development that the Christian era represents. How did it come about when it did? What psychic change did it represent? In exploring these questions, Jung (1875-1961) draws upon Christian symbolism and, in particular, the figure of Christ as a case study in the archetype of the Self. 

Schopenhauer was just 30 when his magnum opus, Die Welt als Wille und Vorstellung, a work of considerable learning and innovation of thought, first appeared in 1818.

Much to his chagrin and puzzlement (so convinced was he of its merits), it didn't have an immediate effect on European philosophy, views and culture. It was only decades later that it was recognised as one of the major intellectual landmarks of the 19th century.

One of the most influential works of this century, The Myth of Sisyphus and Other Essays is a crucial exposition of existentialist thought. Influenced by works such as Don Juan and the novels of Kafka, these essays begin with a meditation on suicide; the question of living or not living in a universe devoid of order or meaning.  

Nietzsche never recovered from his mental breakdown in 1889 and therefore was unable to further any plans he had for the ‘magnum opus’ he had once intended, bringing together in a coherent whole his mature philosophy. It was left to his close friend Heinrich Köselitz and his sister Elizabeth Förster-Nietzsche to go through the remaining notebooks and unpublished writings, choosing sections of particular interest to produce The Will to Power, giving it the subtitle An Attempted Transvaluation of All Values. 

Widely recognized as the finest definition of existentialist philosophy ever written, this book introduced existentialism to America in 1958. Irrational Man begins by discussing the roots of existentialism in the art and thinking of Augustine, Aquinas, Pascal, Baudelaire, Blake, Dostoevski, Tolstoy, Hemingway, Picasso, Joyce, and Beckett. The heart of the book explains the views of the foremost existentialists - Kierkegaard, Nietzsche, Heidegger, and Sartre. The result is a marvelously lucid definition of existentialism and a brilliant interpretation of its impact.

In 1929, Martin Heidegger (1889-1976) published his remarkable book Kant and the Problem of Metaphysics. The Kantbuch, as Heidegger often called it, is regarded by many as a vital supplement to the unfinished second part of Heidegger’s most influential work, Being and Time, which was published two years earlier in 1927.