ARC Triangle

The following is a definition from the Scientology glossary:

ARC triangle: a triangle which is a symbol of the fact that affinity, reality and communication act together as a whole entity and that one of them cannot be considered unless the other two are also taken into account. Without affinity there is no reality or communication. Without reality or some agreement, affinity and communication are absent. Without communication there can be no affinity or reality. It is only necessary to improve one corner of this very valuable triangle in Scientology in order to improve the remaining two corners.

Have you ever sat next to someone on a jet flight and started up a conversation (communication corner) and found out you agreed about many things that are important to you (shared a common reality)? Did you notice that your affinity for the person went from "he/she is a total stranger" to really liking the person enough to exchange cards to keep in touch? Chances are you felt this person understood you as well, didn't you?

That's one example of ARC in action.