For instance, in Descartes' The Passions of the Soul, his "moral concerns lead him to describe the passion of love as altruistic and involving self-sacrifice [but] his general account of passions, however, suggests that all passions (including love) spring from and promote self-interest," leading to a seeming contradiction and debate that ultimately only serves to reinforce outdated notions of love (Frierson 314). This kind of debate around love has allowed different groups, with religions foremost among them, to use love as a means of controlling the populace and their interpersonal lives.
By suggesting that love requires self-sacrifice, one may use another's love in order to get them to do things that they would normally reject outright, and by simultaneously claiming that love stems from some sort of nearly-uncontrollable passion, one may use love as a means of shaming individuals. By describing love solely as the emotions felt and the chemical processes that make up those emotions, one is able to sidestep these moralizing arguments such that one can describe and discuss love without making any claims as to what should be considered "legitimate" or "true" love. The current debate in the United States regarding the legalization of gay marriage stems from this problem, because the underlying argument against gay marriage is that love between two people of the same sex is somehow less legitimate that love between one male and one female. With the stricter definition proposed here, this debate is rendered moot, because the only people who define the legitimacy of the love they feel are the couple in question, and it is left entirely up to them whether they would like to participate in a traditional marking of that experience, just as those ostensibly heterosexual people who go through a starter marriage may choose whether or not they would like to participate in that same tradition.
Though somewhat less prevalent of an issue when describing love, one final thing must be added in regards to the definition of love proposed here. Because it depends solely on the emotional and physiological experience of an individual, and it does not make any judgements regarding the possible legitimacy or illegitimacy of that feeling of love, the definition of love proposed here must necessarily include those instances of attraction which many would rather not be included, such as the feelings a pedophile might propose to have for child, or a rapist for a victim. However, distasteful as this might be for some, it remains necessary to include these possibilities if one desires to have a definition of love that is actually useful. For instance, knowing whether or not a criminal loves his or her victim is exponentially more helpful than simply disregarding his or her given state of mind as inaccurate or otherwise distasteful (remember, as the definition of love proposed here includes chemical experience of love, knowing someone is in love reveals important information about his or her stability and susceptibility to reason). Despite the inclination to say "that's not love" (much in the same way people often say "that's not art"), recognizing that love is an emotional and chemical experience offers the only useful way of understanding the concept as it applies across the entire spectrum of human experience.
Despite the fear that the essence of love is nigh indefinable and the prevalence of idealized notions of love that have no bearing to the realities of human experience, determining a specific, productive definition of love is possible. By recognizing that love is a collection of emotions and chemical changes characterized by certain behaviors and feelings towards other individuals allows one to discuss love without falling into any of the same traps of categorization and distinction which previously hindered a useful consideration of love. Ignoring the outdated notions of love and the rules for determining its legitimacy in the eyes of moralizing institutions allows one to apply this proposed definition of love in order to explain not only recent trends in marriage and divorce rates but also how it can improve society at large by taking better consideration of people's state of mind in an objective, productive way.
Frierson, Patrick. "Learning to Love: From Egoism to Generosity in Descartes." Journal of the History of Philosophy. 40.3 (2002): 313-338. Print.
Gottschall, Jonathan, and Marcus NordlandLast. "Romantic Love: A Literary Universal? ."