love

love is

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.[1][2] 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.[3]
Love is considered to be a positive and negative: with its virtue representing human kindness, compassion, and affection, as "the unselfish loyal and benevolent concern for the good of another"; and its vice representing human moral flaw, akin to vanity, selfishness, amour-propre, and egotism, as it potentially leads people into a type of mania, obsessiveness or codependency.[4][5] It may also describe compassionate and affectionate actions towards other humans, one's self or animals.[6] In its various forms, love 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.[7] 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 (in Greek, Storge), friendly love or platonic love (Philia), romantic love (Eros), guest love (Xenia) and divine love (Agape). Modern authors have distinguished further varieties of love: unrequited love, empty love, companionate love, consummate love, infatuated love, self-love, and courtly love. Numerous cultures have also distinguished Ren, Yuanfen, Mamihlapinatapai, Cafuné, Kama, Bhakti, Mettā, Ishq, Chesed, Amore, Charity, Saudade (and other variants or symbioses of these states), as culturally unique words, definitions, or expressions of love in regards to a specified "moments" currently lacking in the English language.
Scientific research on emotion has increased significantly over the past two decades. The color wheel theory of love defines three primary, three secondary and nine tertiary love styles, describing them in terms of the traditional color wheel. The triangular theory of love suggests "intimacy, passion and commitment" are core components of love. 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.  

Definitions 

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.[12] Cultural differences in conceptualizing love thus doubly impede the establishment of a universal definition.[13]

Although the nature or essence of love is a subject of frequent debate, different aspects of the word can be clarified by determining what isn't love (antonyms of "love"). Love as a general expression of positive sentiment (a stronger form of like) is commonly contrasted with hate (or neutral apathy). As a less-sexual and more-emotionally intimate form of romantic attachment, love is commonly contrasted with lust. As an interpersonal relationship with romantic overtones, love is sometimes contrasted with friendship, although the word love is often applied to close friendships or platonic love. (Further possible ambiguities come with usages "girlfriend", "boyfriend", "just good friends"). 

 Abstractly discussed, love usually refers to an experience one person feels for another. Love often involves caring for, or identifying with, a person or thing (cf. vulnerability and care theory of love), including oneself (cf. narcissism). In addition to cross-cultural differences in understanding love, ideas about love have also changed greatly over time. Some historians date modern conceptions of romantic love to courtly Europe during or after the Middle Ages, although the prior existence of romantic attachments is attested by ancient love poetry.[14]

The complex and abstract nature of love often reduces discourse of love to a thought-terminating cliché. Several common proverbs regard love, from Virgil's "Love conquers all" to The Beatles' "All You Need Is Love". St. Thomas Aquinas, following Aristotle, defines love as "to will the good of another."[15] Bertrand Russell describes love as a condition of "absolute value," as opposed to relative value.[citation needed] Philosopher Gottfried Leibniz said that love is "to be delighted by the happiness of another."[16] Meher Baba stated that in love there is a "feeling of unity" and an "active appreciation of the intrinsic worth of the object of love."[17] Biologist Jeremy Griffith defines love as "unconditional selflessness".[18]
Biological basis

Biological models of sex tend to view love as a mammalian drive, much like hunger or thirst.[21] Helen Fisher, an anthropologist and human behavior researcher, divides the experience of love into three partly overlapping stages: lust, attraction, and attachment. Lust is the feeling of sexual desire; romantic attraction determines what partners mates find attractive and pursue, conserving time and energy by choosing; and attachment involves sharing a home, parental duties, mutual defense, and in humans involves feelings of safety and security.[22] Three distinct neural circuitries, including neurotransmitters, and three behavioral patterns, are associated with these three romantic styles.

Lust is the initial passionate sexual desire that promotes mating, and involves the increased release of chemicals such as testosterone and estrogen. These effects rarely last more than a few weeks or months. Attraction is the more individualized and romantic desire for a specific candidate for mating, which develops out of lust as commitment to an individual mate forms. Recent studies in neuroscience have indicated that as people fall in love, the brain consistently releases a certain set of chemicals, including the neurotransmitter hormones, dopamine, norepinephrine, and serotonin, the same compounds released by amphetamine, stimulating the brain's pleasure center and leading to side effects such as increased heart rate, loss of appetite and sleep, and an intense feeling of excitement. Research has indicated that this stage generally lasts from one and a half to three years.[23]

Since the lust and attraction stages are both considered temporary, a third stage is needed to account for long-term relationships. Attachment is the bonding that promotes relationships lasting for many years and even decades. Attachment is generally based on commitments such as marriage and children, or on mutual friendship based on things like shared interests. It has been linked to higher levels of the chemicals oxytocin and vasopressin to a greater degree than short-term relationships have.[23] Enzo Emanuele and coworkers reported the protein molecule known as the nerve growth factor (NGF) has high levels when people first fall in love, but these return to previous levels after one year