DISCLAIMER: This is by no means authoritive and has not been thoroughly researched whatsoever. Use of ideas or principles stated in this theory may cause depression, heartache, and attacks from your girlfriend or boyfriend (if you have one, which is unlikely once you finish this).
Introduction
The Attractivity Theory is Tito's own theory on love, relationships, and dating. It is based on a few founding principles, which go on to establish other extensions of the basic idea. It is helpful for getting rid of your current significant others, driving away potential stalkers, and being cynical about pretty much all dating practices.
The Law of Attractivity
The basic principle of the Attractivity Theory is the Law of Attractivity. The Law of Attractivity states that a person's total attractivity (numerical level of attractiveness) is equal to the sum of a person's physical attractivity multiplied by four and a person's intellectual attractivity, as perceived by another person.
(4 x AP) + AI = AT
A person's physical attractivity is multiplied by four because people value physical appeal more than intellectual appeal. For example, sitting near someone one finds attractive causes a good deal more happiness than talking to the person on the phone while they are on a plane to Denver. A person's physical presence and appearance clearly hold more psychological weight in the Law of Attractivity than intellectual appeal does. This explains why people value physical interactions as much as they do (we're not talking about the more involved ones, you pervs; more like kissing and the like): if intellectual attractivity was more important to people than physical attractivity, then people would find talking or swapping jokes more romantical than kissing under the night sky while listening to old classical music and watching fireworks on the Fourth of July.
This, so far, is all well and good. However, this is but a foretaste of the full application of the Law of Attractivity.
The Equality Principle
The Equality Principle is the backbone of all that is encompassed by the Attractivity Theory. The Equality Principle states that people only enjoy dating people who they perceive as having an equal or greater total attractivity as themselves.
For example, let's take the case of Zaphod. Zaphod is a swell, good-looking guy. He looks around a room full of girls and finds the one whose physical attractivity equals his self-perceived total attractivity. The reason that he only bases his selection on physical attractivity is that he can only perceive physical attractivity from a distance. Unless Zaphod goes up to the girl and talks to her, he cannot perceive her intellectual attractivity. Thus, it can be assumed that first impressions are based solely on physical attractivity, and lack any built-in intellectual value. This concept will prove very significant in the later part of this theory.
The Equality Principle can be written in the following form:
(4 x AP1 + AI1) = (4 x AP2 + AI2)
How the Equality Principle Works
The Equality Principle can be used to explain the behavioral patterns of romantical relationships.
For example, let's say that our friend Zaphod decides to ask Trillian, the girl he picked out of the room, to be his girlfriend. If Trillian subconciously calculates Zaphod's total attractivity to be equal to her own, then she will say yes. Otherwise, she will most likely say no.
(Sometimes, people act in ways that are contrary to what they think, feel, or believe. This is known as "leading someone on," "sending someone to their guillotine of depression," and many other very depressing phrases that this theory does not intend to cover. The Equality Principle does not cover such cases of trickery, as they are often very difficult to understand, or even grasp at a basic level.)
If Trillian says yes, then the Equality Principle will begin to show up in obvious action. First, Zaphod and Trillian will get to know each other. Their new knowledge of the other's intellectual attractivity will cause them to re-evaluate the other's total attractivity. Often, this causes the equality of the couple's total attractivities to fall out of place and become imbalanced. It does not matter how hard a person tries at this point, because the equality of attractivity has been lost. This accounts for why so many relationships fall apart once the two people get to know each other.
Explanations to Key Phrases
A few phrases have been used throughout history when the equality of a couple's attractivity is lost. Unfortunately, one person must always bring the subject to the discussion floor, and the other must inevitably feel guilt and sorrow for many weeks/months/years to come.
Some commonly used phrases are:
"You've changed since we started dating."
"I don't feel the same as I used to."
"Where's the romance in our relationship?"
"I think we should stop seeing each other for a while."
Luckily for scholars of dating phenomena, these phrases can be boiled down to only one: "When we started dating, I thought you were as awesome or more awesome than me. But now, I don't. So forget we were ever together." As you can see, this generic meaning to all inequality phrases is based directly off of the formula of the Equality Principle. The general idea is that once you have gotten to know a person, you realize their personality flaws, and thus subtract points from their total attractivity. Even if Zaphod likes Trillian more because of her intellectual attractivity, Trillian will likely like Zaphod less, because in her view his attractivity is now less than hers.
(There are some very rare cases where both people involved end up with the same attractivity level even after they get to know each other. While the Theory of Attractivity cannot currently explain such cases, our top researchers are on the job looking for the answer.)
Conclusion
The Attractivity Theory is a proven fact all over the world, and while many have tried, none have been able to escape the vicious rules of the Attractivity Theory. It is a horrific, vicious cycle of doom that controls the system we currently know as "dating." Many people are helpless and uneducated about the process they live through day by day. Hopefully, through the spreading of this theory, a perfect solution to dissolve the Equality Principle will be found. Until then, relationships will basically be doomed from their conception.