In psychology, the term "Oceanic Feeling" was introduced by Roman Rolland to describe the common human psychological feeling marked by religiosity, limitlessness and oneness. This innate feeling is shared by millions of humans and basically makes one feel a sense of oneness and solidarity with the entire human race. He believes that this Oceanic Feeling pervades in all religious systems, rendering them with immense religious energy. The concept of “Oceanic Feeling” was also taken up by the famous psychologist Sigmund Freud in some of his books like Civilization and its Discontents (1929-30) and The Future of an Illusion (1927). In Civilization and its Discontents, he writes-
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.
Freud criticizes excessive religious zeal or religiosity, blaming them for causing delusion and escapist tendencies in humans. He takes up the concept of Oceanic Feeling by relating it with psychoanalytic experience. Further, he identifies the feeling of oneness and unity with the whole world through his concept of infantile narcissism.
Oceanic feeling is a term made by Romain Rolland which criticizes the psychological feeling of religion. Just like the ocean, therefore "oceanic", the feeling is vast or limitless. This feeling is as if someone is connected to another world. Freud on the other hand believed it is harder to experience these feelings and believes it is harder to analyze emotions scientifically.