Existentialism, perhaps to an extent unprecedented in the history of philosophy, has managed to capture the attention of the general public. Estimates of the number of people at Jean-Paul Sartre's funeral in 1980 vary from 50,000 to 100,000, and this was well after his cultural and intellectual heyday. Simone de Beauvoir's famous treatise on the situation of women, The Second Sex, has been one of the most widely read non-fiction books of the twentieth century. Existential plays and novels – in particular Sartre's Nausea and Albert Camus's The Outsider – have been read voraciously and critically acclaimed. Sartre and his more academically inclined colleague Maurice Merleau-Ponty were the co-editors of the influential magazine Les Temps modernes, which considered all things philosophical, political and aesthetic, providing an intellectual point of reference for much of France. Without quite the same mainstream accessibility, or the literary bent (notwithstanding his preoccupation with poetry), Martin Heidegger has been enormously influential on generations of philosophers, as well as people working in cognitive science and artificial intelligence, and his work has helped to spawn at least two very significant contemporary philosophical movements: hermeneutics and deconstruction.

There are obviously many reasons for this primarily philosophical phenomenon capturing the attention of the public in the way that existentialism did, not least the Second World War and the German occupation of France, which intensified existential concerns with freedom, responsibility and death. The literary manifestations of existentialism also allowed a greater proportion of people to possess at least a tentative grasp of what it meant and certainly a greater grasp than might have been attained through the sometimes obscure philosophy of Heidegger, Sartre, Merleau-Ponty and de Beauvoir.