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.

Here are three key works by Sigmund Freud which, published in the first decades of the 20th century, underpinned his developing views and had such a dramatic effect on world society. In the uncompromising Three Essays on the Theory of Sexuality (1905), he declared that 'sexual aberrations' are not limited to the insane but exist in 'normal' people to a greater or lesser degree. The three essays are divided between sexual perversions, childhood sexuality and puberty.

This series of 28 lectures was given by Sigmund Freud (1856-1939), the founder of psychoanalysis, during the First World War and first published in English in 1920. The purpose of this general introduction was to present his work and ideas - as they had matured at that point - to a general public; and even though there was to be considerable development and change over the ensuing years, these talks still offer a valuable and remarkably approachable entry point to his revolutionary concepts.

The most important book ever written in psychology.

As former tutor and adviser to Emperor Nero, philosopher and statesman Seneca was acutely aware of how short life can be - his own life was cut short when the emperor ordered him to commit suicide (for alleged involvement in a conspiracy). And Seneca proved true to his words - his lifelong avowal to Stoicism enabled him to conduct himself with dignity to the end. During his rich and busy life, Seneca wrote a series of essays that have advised and enriched the lives of generations down to the present day.

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.

Awe and exhilaration—along with heartbreak and mordant wit—abound in Lolita, which tells the story of the aging Humbert Humbert's obsession for the nymphet Dolores Haze. Lolita is also the story of a hypercivilized European colliding with the cheerful barbarism of postwar America.

The Red Book, published to wide acclaim in 2009, contains the nucleus of C. G. Jung's later works. It was here that he developed his principal theories of the archetypes, the collective unconscious, and the process of individuation that would transform psychotherapy from treatment of the sick into a means for the higher development of the personality.

At the beginning of his career, Joseph Campbell developed a lasting fascination with the cultures of the Far East, and explorations of Buddhist and Hindu philosophy later became recurring motifs in his vast body of work. However, Campbell had to wait until middle age to visit the lands that inspired him so deeply. In 1954, he took a sabbatical from his teaching position and embarked on a year-long voyage through India, Thailand, Cambodia, Burma, Hong Kong, Taiwan, and finally Japan.

One of Freud's central achievements was to demonstrate how unacceptable thoughts and feelings are repressed into the unconscious, from where they continue to exert a decisive influence over our lives. This volume contains a key statement about evidence for the unconscious and how it works, as well as major essays on all the fundamentals of mental functioning. Freud explores how we are torn between the pleasure principle and the reality principle, how we often find ways both to express and to deny what we most fear and why certain men need fetishes for their sexual satisfaction.