Perhaps one of the most revolutionary works of philosophy ever presented, The Phenomenology of Spirit is Hegel's 1807 work that is in numerous ways extraordinary. A myriad of topics are discussed, and explained in such a harmoniously complex way that the method has been termed Hegelian dialectic. Ultimately, the work as a whole is a remarkable study of the mind's growth from its direct awareness to scientific philosophy, proving to be a difficult yet highly influential and enduring work.

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.’

Friedrich Nietzsche (1844-1900) has influenced philosophers such as Martin Heidegger, Jean-Paul Sartre, Oswald Spengler, George Grant, Emil Cioran, Albert Camus, Ayn Rand, Jacques Derrida, Leo Strauss, Max Scheler, Michel Foucault and Bernard Williams. His writings on aesthetics, language, truth, morality, cultural theory, history, nihilism, power, and the meaning of existence have exerted a vast influence on Western philosophy and intellectual history. 

The Decline of the West - Volume 1 published in 1917, Volume 2 in 1922 - has exercised and challenged opinion ever since. It was a huge undertaking by Oswald Spengler (1880-1936), formerly an unpublished historian and philosopher who set out to radically reconsider history - the rise and fall of world civilisations and their cultures. His primary view was to reject the established Eurocentric paradigm (ancient/classical, Medieval - and, following the Renaissance - modern) and to take a totally new perspective.

In On the Genealogy of Morals, subtitled "A Polemic", Nietzsche furthers his pursuit of a clarity that is less tainted by imposed prejudices. He looks at the way attitudes towards 'morality' evolved and the way congenital ideas of morality were heavily colored by the Judaic and Christian traditions.

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’. 

From a gripping exploration of morality to a deep dive into theoretical reasoning and metaphysics, the philosophy of Immanuel Kant has stood the test of time and made him one of the most famous and influential philosophers of the 18th century. Now, this brilliant collection compiles his writings for modern listeners, a testament to the lasting influence of his ideas and inspirations.

What is life? What is my place in it? What choices do these questions obligate me to make? More than a half-century after it burst upon the intellectual scene - with roots that extend to the mid-19th century - Existentialism's quest to answer these most fundamental questions of individual responsibility, morality, and personal freedom, life has continued to exert a profound attraction.

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. 

What does it mean to say that we live in a secular age? Almost everyone would agree that we - in the West, at least - largely do. And clearly the place of religion in our societies has changed profoundly in the last few centuries. In what will be a defining book for our time, Charles Taylor takes up the question of what these changes mean - of what, precisely, happens when a society in which it is virtually impossible not to believe in God becomes one in which faith, even for the staunchest believer, is only one human possibility among others.

Sigmund Freud (1856-1939) is remembered as the father of psychoanalysis. Civilization and Its Discontents (1930) is one of his key works, written three decades after his seminal book The Interpretation of Dreams. In it he considers the conflict between the needs of the individual acting both egotistically and altruistically in the pursuit of happiness and the myriad demands of civilised society and the ensuing tensions this clash of needs and demands generates. 

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.

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.

Finnegans Wake is the greatest challenge in 20th-century literature. Who is Humphrey Chimpden Earwicker? And what did he get up to in Phoenix Park? And what did Anna Livia Plurabelle have to say about it? In the rich nighttime and the language of dreams, here are history, anecdote, myth, folk tale and, above all, a wondrous sense of humor, colored by a clear sense of humanity. In this exceptional reading by the Irish actor Barry McGovern, with Marcella Riordan, the world of the Wake is more accessible than ever before. 

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.