Love

==Interpersonal==
{{Close Relationships|emotions}}
Interpersonal love refers to love between human beings. It is a much more potent sentiment than ''liking'' a person. [[Unrequited love]] refers to feelings of love that are not reciprocated. Interpersonal love is most closely associated with [[interpersonal relationship]]s.{{r|Fromm}} Such love might exist between family members, friends, and couples. There are several psychological disorders related to love, such as [[erotomania]].

Throughout history, philosophy and religion have speculated about the phenomenon of love. In the 20th century, the science of [[psychology]] has studied the subject. The sciences of [[anthropology]], [[neuroscience]], and biology have also added to the understanding of the concept of love.

===Biological basis===
{{Main|Biological basis of love}}
Biological models of sex tend to view love as a [[mammal]]ian{{clarify|reason=do other classes of animal not have hunger or thirst?|date=August 2023}} drive, much like hunger or thirst.<ref name="Lewis">{{cite book | last1 = Lewis | first1 = Thomas |last2=Amini|first2= F. |last3=Lannon|first3= R. | title = A General Theory of Love | publisher = Random House | year = 2000 |isbn=978-0-375-70922-7| title-link = A General Theory of Love }}</ref> [[Helen Fisher (anthropologist)|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 find attractive and pursue, {{clarify|text=conserving time and energy by choosing|reason=it's not clear what this phrase is doing here|date=August 2023}}; and attachment involves sharing a home, parental duties, mutual defense, and in humans involves feelings of safety and security.<ref name="brain systems">
{{cite journal|url=http://homepage.mac.com/helenfisher/archives_of_sex_beh.pdf |title=Defining the Brain Systems of Lust, Romantic Attraction, and Attachment |access-date=3 October 2011 |url-status=dead |archive-url=https://web.archive.org/web/20110628051603/http://homepage.mac.com/helenfisher/archives_of_sex_beh.pdf |archive-date=28 June 2011|journal=Archives of Sexual Behavior|volume=31|number=5|year=2002|first1=Helen E.|last1=Fisher|first2=Arthur|last2=Aron|first3=Debra|last3=Mashek|first4=Haifang|last4=Li|first5=Lucy L.|last5=Brown |pages=413–419 |doi=10.1023/A:1019888024255 |pmid=12238608 |s2cid=14808862 }}</ref> Three distinct neural circuitries,{{Specify|date=August 2023}} including neurotransmitters,{{Specify|date=August 2023}} and three behavioral patterns,{{Specify|date=August 2023}} are associated with{{How|date=August 2023}} these three romantic styles.<ref name="brain systems"/>

[[File:Gothaer Liebespaar.jpg|thumb|left|180px|''Pair of Lovers''. 1480–1485]]
[[Lust]] is the initial passionate sexual desire that promotes [[Mating (human)|mating]], and involves the increased release of [[hormones]] such as [[testosterone]] and [[estrogen]]. These effects rarely last more than a few weeks or months. [[Interpersonal attraction|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 form. Recent studies in [[neuroscience]] have indicated that as people fall in love, the brain consistently releases a certain set of chemicals, including the [[neuroendocrine|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]], [[Anorexia (symptom)|reduced appetite]] and [[insomnia|sleep]], and an [[euphoria|intense feeling of excitement]]. Research indicates that this stage generally lasts from one and a half to three years.<ref name="human">{{cite book | publisher=Holt, Rinehart, & Winston | title=Holt World History: The Human Legacy | date=2008-01-01 | isbn=978-0-03-093780-4 }}</ref>

Since the lust and attraction stages are both considered temporary, a third stage is needed to account for long-term relationships. [[Attachment theory|Attachment]] is the [[human bonding|bonding]] that promotes relationships lasting for many years and even decades. Attachment is generally based on commitments such as marriage and children, or 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 what is found in short-term relationships.<ref name="human"/> [[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.<ref>{{cite journal|last1=Emanuele|first1= E.|last2=Polliti|first2= P.|last3=Bianchi|first3= M.|last4=Minoretti|first4= P.|last5=Bertona|first5= M.|last6=Geroldi|first6= D.|year=2005|title=Raised plasma nerve growth factor levels associated with early-stage romantic love|url=https://www.sciencedirect.com/science/article/abs/pii/S0306453005001976|journal=Psychoneuroendocrinology|doi=10.1016/j.psyneuen.2005.09.002|volume=31|pmid=16289361|issue=3|pages=288–294|s2cid=18497668|access-date=3 December 2006|archive-url=https://web.archive.org/web/20061206142641/http://www.biopsychiatry.com/lovengf.htm|archive-date=6 December 2006|url-status=live}}</ref>
{{clear}}

===Psychological basis===
{{Further|Human bonding}}
[[File:Sri Lankan woman and child.jpg|thumb|Grandmother and grandchild in [[Sri Lanka]]]]
[[Psychology]] depicts love as a cognitive and social phenomenon. [[Psychologist]] [[Robert Sternberg]] formulated a [[triangular theory of love]] in which love has three components: intimacy, commitment, and passion. Intimacy is when two people share confidences and various details of their personal lives, and is usually shown in friendships and romantic love affairs. Commitment is the expectation that the relationship is permanent. Passionate love is shown in infatuation as well as romantic love. All forms of love are viewed as varying combinations of these three components. Non-love does not include any of these components. Liking only includes intimacy. Infatuated love only includes passion. Empty love only includes commitment. Romantic love includes both intimacy and passion. Companionate love includes intimacy and commitment. Fatuous love includes passion and commitment. Consummate love includes all three components.<ref>{{cite journal | last=Sternberg| first= R.J. |year=1986| title=A triangular theory of love| journal=Psychological Review|volume= 93 |issue=2|pages= 119–135| doi= 10.1037/0033-295x.93.2.119}}</ref>

American psychologist [[Zick Rubin]] sought to define ''love'' by [[psychometrics]] in the 1970s. His work identifies a different set of three factors that constitute love: attachment, caring, and intimacy.<ref>{{multiref2
|1={{cite journal|last=Rubin|first=Zick|title=Measurement of Romantic Love|journal=Journal of Personality and Social Psychology|volume=16|pages=265–273|year=1970|doi=10.1037/h0029841|pmid=5479131|issue=2|citeseerx=10.1.1.452.3207}}
|2={{cite book|last=Rubin|first=Zick|title=Liking and Loving: an invitation to social psychology|url=https://archive.org/details/likinglovinginvi00rubi|url-access=registration|location=New York|publisher=Holt, Rinehart & Winston|year=1973|isbn=978-0030830037}} }}</ref>

Following developments in electrical theories such as [[Coulomb's law]], which showed that positive and negative charges attract, analogs in human life were envisioned, such as "opposites attract". Research on human mating has generally found this not to be true when it comes to character and personality—people tend to like people similar to themselves. However, in a few unusual and specific domains, such as [[immune system]]s, it seems that humans prefer others who are unlike themselves (e.g., with an orthogonal immune system), perhaps because this will lead to a baby that has the best of both worlds.<ref>{{cite book | last1 = Berscheid | first1 = Ellen | author-link1 = Ellen S. Berscheid |last2=Walster|first2= Elaine H. | title = Interpersonal Attraction | publisher = Addison-Wesley Publishing Co | year = 1969 | lccn = 69-17443 | isbn = 978-0-201-00560-8 }}</ref>

In recent years, various [[human bonding]] theories have been developed, described in terms of attachments, ties, bonds, and affinities.
Some [[Western culture|Western]] authorities {{clarify|text=disaggregate|reason=disaggregate what?|date=August 2023}} into two main components, the altruistic and the narcissistic. This view is represented in the works of [[M. Scott Peck|Scott Peck]], whose work in the field of [[applied psychology]] explored the definitions of love and evil. Peck maintains that love is a combination of the "concern for the spiritual growth of another" and simple narcissism.<ref name="peck">{{cite book | title=The Road Less Traveled | isbn=978-0-671-25067-6 | last=Peck | first=Scott | publisher=Simon & Schuster | year=1978 | page=[https://archive.org/details/roadlesstraveled00peck_0/page/169 169] | url=https://archive.org/details/roadlesstraveled00peck_0/page/169 }}</ref> In combination, love is an ''activity'', not simply a feeling.

Psychologist [[Erich Fromm]] maintained in his book ''[[The Art of Loving]]'' that love is not merely a feeling but is also actions, and that in fact the "feeling" of love is superficial in comparison to one's commitment to love via a series of loving actions over time.{{r|Fromm}} Fromm held that love is ultimately not a feeling at all, but rather is a commitment to, and adherence to, loving actions towards another, oneself, or many others, over a sustained duration.{{r|Fromm}} Fromm also described love as a conscious choice that in its early stages might originate as an involuntary feeling, but which then later no longer depends on those feelings, but rather depends only on conscious commitment.{{r|Fromm}}

===Evolutionary basis===
[[File:Place des Abbesse (the plaque with the je t'aime=te iubesc in 311 laguages).jpg|thumb|''[[Wall of Love]]'' on [[Montmartre]] in Paris: "I love you" in 250 languages, by calligraphist Fédéric Baron and artist Claire Kito (2000)]]

[[Evolutionary psychology]] has attempted to provide various reasons for love as a survival tool. Humans are dependent on parental help for a large portion of their lifespans compared to other mammals. Love has therefore been seen as a mechanism to promote parental support of children for this extended time period. Furthermore, researchers as early as [[Charles Darwin]] identified unique features of human love compared to other mammals and credited love as a major factor for creating social support systems that enabled the development and expansion of the human species.{{citation needed|date=January 2023}} Another factor may be that [[sexually transmitted disease]]s can cause, among other effects, permanently reduced [[fertility]], injury to the fetus, and increase complications during [[childbirth]]. This would favor monogamous relationships over [[polygamy]].<ref>{{cite book|title=The Handbook of Evolutionary Psychology|editor-first=David M.|editor-last=Buss|publisher=John Wiley & Sons, Inc.|year=2005|chapter=Commitment, Love, and Mate Retention|first1=Lorne|last1=Campbell|first2=Bruce J.|last2=Ellis}}</ref>

===Adaptive benefit===
Interpersonal love between a man and woman provides an evolutionary adaptive benefit since it facilitates mating and [[sexual reproduction]].<ref name = Michod1989>{{cite journal|last=Michod|first=Richard E.|title=What's love got to do with it? The solution to one of evolution's greatest riddles|journal=The Sciences|year=1989|pages=22–27|doi=10.1002/j.2326-1951.1989.tb02156.x}}</ref> However, some organisms can reproduce [[asexual reproduction|asexually]] without mating. Understanding the adaptive benefit of interpersonal love depends on understanding the adaptive benefit of sexual reproduction as opposed to asexual reproduction. Richard Michod reviewed evidence that love, and consequently sexual reproduction, provides two major adaptive advantages.{{r|Michod1989}} First, sexual reproduction facilitates [[DNA repair|repair of damages in the DNA]] that is passed from parent to progeny (during [[origin and function of meiosis|meiosis]], a key stage of the sexual process). Second, a gene in either parent may contain a harmful [[mutation]], but in the progeny produced by sexual reproduction, expression of a harmful mutation introduced by one parent is likely to be masked by expression of the unaffected homologous gene from the other parent.{{r|Michod1989}}

===Comparison of scientific models===
Biological models of love tend to see it as a {{clarify|text=mammalian|reason=why should we expect other classes of animal not to have hunger or thirst?|date=August 2023}} drive, similar to hunger or thirst.<ref name="Lewis"/> Psychology sees love as more of a social and cultural phenomenon. Love is influenced by [[hormone]]s (such as [[oxytocin]]), [[neurotrophins]] (such as [[nerve growth factor|NGF]]), and [[pheromone]]s, and how people think and behave in love is influenced by their conceptions of love. The conventional view in [[biology]] is that there are two major drives in love: [[sexual attraction]] and [[attachment theory|attachment]]. Attachment between adults is presumed to work on the same principles that lead an infant to become attached to its mother. The traditional psychological view sees love as being a combination of [[companionate love]] and passionate love. Passionate love is intense longing, and is often accompanied by [[physiological arousal]] (shortness of breath, rapid heart rate); companionate love is affection and a feeling of intimacy not accompanied by physiological arousal.

===Health===
The psychologist [[Abraham Maslow]] identified a person feeling truly loved as a basic and foundational human need.<ref name="Geher, May 2022">{{cite web |url= https://www.psychologytoday.com/us/blog/darwins-subterranean-world/202205/the-psychology-feeling-unloved |title= The Psychology of Feeling Unloved |last= Geher |first= Glenn |date= 27 May 2022 |website= psychologytoday.com |publisher= Psychology Today |access-date= 19 January 2024}}</ref> Love has been found to have a strong correlation to happinness and being able to build relationships and develop communities.<ref name="Geher, May 2022"/> Adverse effects of feeling unloved can result in conditions such [[post-traumatic stress disorder]] (PTSD).<ref name="Geher, May 2022"/>