A relationship between two or more people.

One person:

1. You're alone, you can do whatever you want. It doesn't infringe on anyone's freedom or rights. Because you're alone. You're free.

Two people (you're interacting with another person):

1: Friendship
1.1: The social relationship needs to benefit you (selfishness)
1.2: The social relationship needs to benefit the other person (altruism)
1.2.x: But what if it's you who needs something (even just company/affection) from others?
1.2.1: Pretend you don't need it. Keep it inside. Only do favors to others, never ask anything in return.
1.2.2: Unless it's something really important, pretend you don't need it and keep it inside. If it's something you desperately need, ask, and MAYBE you'll get it. Maybe.
1.2.2.1: If you don't get what you need when you desperately need it, you won't help others either.
1.2.2.2: Even if you don't get what you need when you desperately need it, you'll still help others.
1.2.3: Unless it's something that is really unimportant, just ask.
1.3: The social relationship needs to benefit both (utilitarianism???)
1.3.1: The social relationship needs to benefit both, but more to yourself (selfish-leaning utilitarianism)
1.3.2: The social relationship needs to benefit both, but more to the other person (altruism-leaning utilitarianism)
1.3.3: The social relationship needs to benefit both equally (equality-based utilitarianism)
1.3.4: The social relationship needs to benefit both, who more depends on the context (context-based utilitarianism)
1.4: Who should benefit from the social relationship depends on the context.
1.4.1: Who should benefit from the social relationship depends on who can 'give' and who needs to 'receive' (i.e. something beneficial... a favor... or even just some company or affection). Kinda like how Marx said 'from each according to their abilities, to each according to their needs'.
1.4.2: Who should benefit from the social relationship depends on how 'worthy' that person is of benefits. This can compound into social hierarchies within a group, and the larger the group, the stricter the hierarchies, but this is for another part of the text. With two people, who should benefit more may be based on the benefit that a person has given to the other person. Of course, with just two people, it is (presumably) equal and transactional, kind of like a symbolic 'currency' between the two people.
1.5: benefit-ratio e.g. (1 = total selfishness, 0 = total-altruism, 0.5 = balanced, 0.75 = selfish-leaning, 0.25 = altruistic-leaning, etc)
1.6: just behave naturally, don't think about these things
1.7: Two criteria: how 'needy' someone is, and how willing to make favors the other person is. The levels of how much someone is a 'giver' and how much one is a 'taker'.
1.8: What if you don't really need anything from the other person?
1.8.1: Then you do favors for that person as long as that doesn't hurt/disadvantage you in any way.
1.8.2: Then you don't do any favors for that person.
1.8.3: Then you do favors for that person even if that hurts/disadvantages you.
1.9: The "formula" changes depending on some factors and is not equal for everyone. What factors?
1.9.1: The level of relationship you have with that person. Ranging from strangers through acquaintances through friends to close friends.
1.9.1.1: Close friends have the greatest benefits from you, strangers have the least (perhaps none at all, in fact, depending on your own selfishness-altruism stats).
1.9.1.1.1: Close friends become such because they have given benefits to you. The more benefits they give you, the higher you rank them on the friendship scale.
1.9.1.1.1.1: Parameter "how much can they give to you" taken into consideration.
1.9.1.1.1.2: Parameter "how much can they give to you" ignored.
1.9.1.1.1.3: Parameter "how much do you need from them" taken into consideration.
1.9.1.1.1.4: Parameter "how much do you need from them" ignored.

Question: why do you say something (as opposed to either not saying anything, or saying something else)?

1: To emanate a certain vibe/aesthetics.
2: To benefit yourself (what kind of benefit?)
2.1: Entertainment
2.2: Requesting to do something that may make you happy or give you some kind of benefit
3: To benefit someone else (what kind of benefit?)
4: To benefit both yourself and someone else (what kind of benefit?)
5: To give more information
6: To contradict the other person's beliefs
6.1: To benefit the other person by providing the correct information
6.2: If the contradicting information provides no benefits but hurts the person emotionally, then:
6.2.1: Say it anyway.
6.2.2: Don't say it.
7: To say something the other person already knows (why exactly? maybe for social bonding?)
7.1: Yes, for social bonding.
7.2: Because you find it satisfying/cathartic to reiterate that statement.

What kind of person you're dealing with (in terms of altruism/selfishness)?

1: Altruistic person (goal: benefitting others)
1.1: Totally altrustic (self-defeating): sacrifices self even to slightly please others.
1.2: Almost totally altruistic (self-defeating): sacrifices self if that causes great benefit to others.
1.3: Non-sacrificial: doesn't sacrifice self no matter how much it benefits others.
2: Selfish person (goal: benefitting self)
1.1: Totally selfish: harms others even to slightly please self
1.2: Almost totally selfish: harms others if that causes great benefit to self.
1.3: Harmless: doesn't harm others no matter how much it benefits self.
3: Sadistic person (goal: harming others)
3.1: Totally sadistic: sacrifices self even to slightly harm others.
3.2: Almost totally sadistic: sacrifices self if that causes great harm to others.
3.3: Non-sacrificial: doesn't sacrifice self no matter how much it harms others.
4: Masochistic person (goal: harming self)
4.1: Totally masochistic person: harms others even to slightly harm self
4.2: Almost totally masochistic person: harms others if that causes great harm to self.
4.3: Harmless (to others): doesn't harm others no matter how much it harms self.
4.4: Suicidial (goal: killing self)
4.5: Self-harm but not suicidial (goal: harming self but not killing self)
5: Variable person (goal: varies)
6: Goal: other
6.1: Hates compliments
6.1.1: Will get offended if you compliment them
6.1.2: Doesn't compliment others
6.1.3: But may compliment others if they want
6.2: Loves compliments
6.2.1: Will get offended if you don't compliment them
6.2.2: Doesn't compliment others
6.2.3: Compliment others as well