Jean-Paul Sartre

Jean-Paul Sartre built a whole philosophy on a single vertigo: that we are condemned to be free, that existence comes before essence, and that we author ourselves through our choices. Born in Paris in 1905 and raised largely by his grandfather after his father's early death, he became the great voice of twentieth-century existentialism, giving us Being and Nothingness, the concept of bad faith, and a lifelong open partnership with Simone de Beauvoir. In 1964 he refused the Nobel Prize, unwilling to be turned into an institution.

His Sun in Gemini, the sign of the messenger and the eternal twin, shines in the seventh house of partnership. Here is the philosopher who understood both sides of every argument, whose identity was lit through the other, above all through Beauvoir. His Moon in Aquarius, the selfless psyche fused with the tribe, sat in the second house, wiring his values not to possessions but to ideas held for all humanity; small wonder he spurned honours and money alike. Sagittarius rising gave him the wandering preacher-philosopher's mask, forever lecturing, forever free. He remains philosophy's restless twin.