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Love encompasses a range of strong and positive emotional and mental states, from the most sublime virtue or good habit, the deepest interpersonal affection and to the simplest pleasure. An example of this range of meanings is that the love of a mother differs from the love of a spouse, which differs from the love of food. Most commonly, love refers to a feeling of strong attraction and emotional attachment.
Love is also considered to be a virtue representing human kindness, compassion, and affection, as "the unselfish loyal and benevolent concern for the good of another". It may also describe compassionate and affectionate actions towards other humans, one's self or animals.
Love in its various forms acts as a major facilitator of interpersonal relationships and, owing to its central psychological importance, is one of the most common themes in the creative arts. Love has been postulated to be a function to keep human beings together against menaces and to facilitate the continuation of the species.
Ancient Greek philosophers identified five forms of love: essentially, familial love , friendly love or platonic love , romantic love , guest love and divine love. Modern authors have distinguished further varieties of love: unrequited love, infatuated love, self-love, and courtly love. Asian cultures have also distinguished Ren, Kama, Bhakti, Mettā, Ishq, Chesed, and other variants or symbioses of these states. Love has additional religious or spiritual meaning. This diversity of uses and meanings combined with the complexity of the feelings involved makes love unusually difficult to consistently define, compared to other emotional states.
The word "love" can have a variety of related but distinct meanings in different contexts. Many other languages use multiple words to express some of the different concepts that in English are denoted as "love"; one example is the plurality of Greek words for "love" which includes agape and eros. Cultural differences in conceptualizing love thus doubly impede the establishment of a universal definition.