Romain Rolland, winner of the 1915 Nobel Prize for Literature, once wrote to his friend Sigmund Freud about that particular sensation that comes over us when we look out to sea. Freud recalls the letter in Civilization and Its Discontents (1929):

"[The true source of religion] consists in a peculiar feeling, which [Rolland] himself is never without, which he finds confirmed by many others, and which he may suppose is present in millions of people. It is a feeling which he would like to call a sensation of ‘eternity’, a feeling as of something limitless, unbounded — as it were, ‘oceanic’. This feeling, he adds, is a purely subjective fact, not an article of faith; it brings with it no assurance of personal immortality, but it is the source of the religious energy which is seized upon by the various Churches and religious systems, directed by them into particular channels, and doubtless also exhausted by them. One may, he thinks, rightly call oneself religious on the ground of this oceanic feeling alone, even if one rejects every belief and every illusion.”