General Description of Activity Relations
Activation, or activity, is an intertype relation between two people that belong to opposite poles of all basic dichotomies except for extraversion and introversion (e.g. SLI, which is introverted, sensing, logical, and irrational, and EII, which is introverted, intuitive, ethical, and rational.) Activation partners belong to the same quadra and thus find it comfortable to let down their guard around each other, making this relationship very easy to start.
Activation is a very common relationship for friendship. Activation is similar to duality in that each person provides those kinds of information that the other most expects, however, the emphasis is always somewhat different than subconsciously expected. Partners are able to provide each other with an abundance of useful information and assistance, but lead separate lives and make decisions based on criteria that don't seem too important to the other.
Activation partners who become close and discuss their strivings and personal worldviews often are struck by how radically different they are, despite the relative ease and benefit of communication. As opposed to duals, who tend to strive for the same things but from differing, though compatible angles, activation partners' approaches to achieving their goals tend to be fundamentally incompatible, due largely to the difference in rationality and irrationality. This means that while activation partners can talk and share their common hobbies with ease, they tend to view each other as separate entities with separate lifestyles and plans.