Love is a word that has a variety of different meanings within different contexts. It is generally defined as a strong affection for another person, be it maternal, sexual, or based on admiration, and is sometimes even extended to objects or even food. There are differences in the concept of love even between cultures and countries, making it difficult to arrive at a "universal" definition of love.
Love is sometimes categorized as either impersonal or interpersonal love. Impersonal love is that for an object, principle, or goal that a person may be deeply committed to or greater value. Examples include the love of "life itself," love for a stuffed animal, or even love for a cause or idea.
Interpersonal love is love between human beings. It can refer to the love that exists between family members, friends, or couples. There has been much speculation throughout history on the basis of love, some of which try to explain love in terms of a biological, psychological, and even evolutionary basis.
Regardless of what any psychologist or "expert" says, how a person views or defines love is up to them, and the results of any online calculator or predictor of love should have little to no bearing on whether or not a person chooses to pursue it.
In general, we are attracted to people like ourselves. Middle-class people go for similarly middle-class types, and we look for those, within our class, who like the same kind of clothes, or music, or environment. Of course, sometimes we find ourselves very attracted to those who are totally unlike us, really opposites, and that's because we seek change and stimulation.
Some say that we seek people like ourselves to form a more stable union and to have children like ourselves. Well-known actresses pair up with rock stars, for example, because such men tend to be as rich and famous as they are.
But the challenge of the unknown is great. Some say that we tend to fall in love with those who are mysterious and challenging to us because they come to us with a very different gene pool. So the children will benefit from broader genetic input. But there's no scientific proof for such assertions.
Physical features are important to both sexes, but a bit more so to men. There is some scientific basis for this. According to Louann Brizendine, a clinical professor of psychiatry at the University of California, San Francisco, and the author of "The Female Brain, the male brain processes the female image, while the female brain takes in a good looking male, but also shows judgmental activity, thinking about the guy's character at the same time.
Love does take over most of your brain activity, Brizendine says, and once it has you hooked, it doesn't let you go. It keeps your chemicals hopping, which is why you can't seem to get the other person out of your head.
But all the scientists admit that there's no real hard explanation for why one person goes for another, as opposed to another one. There will probably never be a science of love, nor any way to calculate what the results will be. So let your mind and your heart decide.