In 1906, the young Swiss psychiatrist Carl Jung received a collection of essays from none other than the founder of psychoanalysis himself, Sigmund Freud. When the two met in person a year later in Vienna, their first conversation lasted more than 13 hours, according to Jung’s account. And so began a collaboration that would blossom into an intense, albeit brief friendship between two titans of psychology. The duo toured the US together, giving lectures on psychoanalysis. They analysed each other’s dreams in depth. Twenty years his senior, Freud called Jung ‘the Joshua to my Moses, fated to enter the Promised Land which I myself will not live to see’. Their bond was so deep that at one point Jung wrote to Freud: ‘Let me enjoy your friendship not as one between equals but as that of father and son.’ Despite their shared interests and mutual admiration, in 1913 their relationship abruptly ended. But what caused their dramatic estrangement? And which one can lay claim to greater influence?

Freud versus Jung is the second instalment of ‘Philosophy Feuds’, Aeon’s original series of short animations, each of which tells the story of a famous – or not so famous – spat, break-up, falling-out or fracas. More than just revealing the hilarious and all-too-human pettiness of the world’s greatest thinkers, ‘Philosophy Feuds’ is about the fascinating ideas behind each of these rifts – and how these ideas continue to matter today.