It was once de rigueur for hipsters to be seen poring over a tatty paperback copy of Jean-Paul Sartre's existential novel Nausea. As a work of literature, the book is a perfect representation of the angst of youth - the difficulty of connecting with people and the apparent pointlessness of existence.
But Sartre wrote the book to lay the foundation for his complex philosophical system. In Nausea, he strips away our reasons for existing to clear the ground for the existential mode of living he develops in his later work. This was Sartre's first published work, written while he was still a philosophy lecturer. He chose to express his ideas in novel form because he believed philosophy had become too detached from everyday life. Novels were a way to reach people other than academics. Although his ideas were later developed in his major work Being and Nothingness, the Frenchman continued to write novels and plays and won a Nobel Prize for literature in 1964.
Nausea is presented in the form of a journal written by protagonist Antoine Roquentin, who records his daily existence in minute detail.
His observations lead him to the conclusion that we can't prove that the outside world exists at all. Following Rene Descartes, the founder of modern philosophy, Roquentin decides the only thing we can be certain exists is ourself - 'I think, therefore I am,' as Descartes reasoned. We are solitary beings without purpose.
Existentialism has seeped so deeply into modern life it's difficult to see how Sartre's views could once have been considered radical. Nausea's big idea is that there is no reason for our existence. Until the 19th century, humankind had been presumed to have been given a special purpose by God. Although atheism had become more common in the late 1800s, atheists had looked to non-religious reasons to give our lives a sense of purpose.
Nausea expresses the cornerstone of Sartre's philosophy that there is absolutely no reason, divine or otherwise, for us to be here. While it's true we do exist, there is no purpose behind our existence. We are just here, and that's as far as it goes. This idea, common today, only became philosophical currency in the early 20th century.
Nausea stops there, but Sartre went on to develop existentialism as a powerful - and positive - philosophy of action. There is no reason for us to exist, he argues, but we do exist. So we must make our own reasons for existing - our own moralities, and our own truths.
Sartre's complex later body of work explains how this can be done. It's a liberating theory that gives everyone the power to bestow meaning and purpose on their lives. Nausea is the first step on our individual road to freedom.