I'm going to answer this question in 2 parts. In the first part, I'll reference Robert Sternberg's triangular
theory of love. Sternberg claims that there are 3 components of consummate love ("true" love). All three components are required, and if even one is missing, then it isn't consummate love. The three components are:
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Intimacy: A feeling of closeness with the other person. It means that, among other things, you feel comfortable enough with this person to discuss things about yourself that you wouldn't discuss with complete strangers. It's about being open with the other person.
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Passion: Passion is attraction. Enough said.
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Commitment: The desire to commit to the relationship in the long term.
A relationship in which only intimacy is present is like to be more of an acquaintance. You might feel comfortable to discuss personal details, but you aren't attracted to them, and it wouldn't really matter if you never saw them again. If only passion is present, then it's called infatuation. Basically, you don't really know the person so you won't share personal details with each other, and you have no intention of maintaining a long-term relationship, but you're really attracted to the other person. If only commitment is present then it is called empty love. You aren't open with the person, and aren't attracted to the person, but you feel that you have an obligation to maintain the relationship. This is often the last stage of a dieing relationship, except in countries with pre-arranged marriages, in which this is the first stage of a relationship.
A relationship with intimacy and passion is called romantic love. This is where you're close with the other person, you're attracted to them, but you don't really have any definite plans on how to maintain the relationship. If passion and commitment are present, it is a fatuous relationship. This is where you're attracted to each other, you have plans to maintain the relationship, but you really aren't open with each other, and can't share anything. Like a lot of celebrity relationships
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. If intimacy and commitment are present, then it is called
companionate love. This is where you're really close with the person, are committed to maintaining the relationship, but you aren't physically attracted to each other. This probably would have been the ideal relationship in ancient Greece, considering the kind of asceticism that was common then.
In the second part, I'm going to completely destroy the concept of love by exploring the
biological basis for love in the brain. Why do scientists have to ruin everything that's good and true in the world?