An apricot cocktail started Jean-Paul Sartre on the road to existentialism.

For a lot of us, existentialism is a murky term, one that suggests gloomy ideas about the futility of life. But existentialism started with something a lot more cheerful: an apricot cocktail.

Around the end of 1932, Jean-Paul Sartre, his girlfriend Simone de Beauvoir and his friend Raymond Aron sat in the Bec-de-Gaz bar in Paris, sipping cocktails and catching up. The three had studied philosophy together at École normale supérieure in Paris, and had graduated restless and unsatisfied. The school’s curriculum was dominated by the same questions that philosophers had been asking since Plato’s time, like “How can I know that things are real?” and “How can I be sure that I know anything for certain?” It was hard to see the point in any of it, and the three friends were hungry for a new kind of philosophy, something that spoke to their dissatisfaction with the stale old questions that had bored them in school.

But what other ways of philosophizing could there be? Sartre and Beauvoir had been teaching in the French provinces since they’d graduated, and neither had any new ideas to report. Aron, though, thought he had found an answer. Studying in Berlin after graduation, he had encountered a new and different philosophy that had originated in Germany: phenomenology. What made phenomenology so exciting was that it put stale metaphysical questions like the ones they’d studied at the École normale supérieure to one side in order to look at the stuff of real, everyday life. With phenomenology, Aron said, he could even use his apricot cocktail to philosophize!

His friends were astounded.

Sartre lit up, and went straight to a bookstore. Hungry to know more about phenomenology, he asked for every book on the topic that the shop had. Unfortunately, that only meant a single book. Though Sartre tore through it, he was desperate to know more; soon he was making arrangements to study in Berlin for a year, just as Aron had. There, Sartre created something entirely new, blending the phenomenology books that he read with other philosophers’ ideas and his own literary style and personality. By the time he returned to Paris in 1934, he was ready to found a new philosophy of his own: existentialism.

Sartre’s year in Berlin had been fruitful. But ironically, a different city in Germany was actually the heart of phenomenology: Freiburg.