There are countless theories on the ideal Enneagram matches out there. Most of those theories are largely based on personal experience. Other experts argue that there are no ideal Enneagram type matches generally, and that it depends on the specific individual and their goals, desires, etc. While I tend to subscribe to the latter position (with the exception that I do believe that certain instinctual stacking pairings are significantly better than others), I have recently thought more about the ideal Enneagram type matches, or in Socionics-infused words, one's "Enneagram Dual".
The problem is, that Enneagram compatibility is not black and white. There are many nuances that must be taken into consideration. And also, the theory must be able to have its roots in reality – meaning, people need to actually be drawn to and experience satisfaction and attraction with those particular matches.
As I was looking up the properties and qualities of the Enneagram types (mainly the canon Harmonic Triad and Hornevian Triad distinctions), I started to see how each of those traits was unconsciously looking for or would at least greatly benefit from their complement.
Before I continue, here a short overview of what the Triads entail:
(how the type deals with life obstacles):
Competency: 1, 3, 5
Positive Outlook: 2, 7, 9
Emotional Realness/Reactivity: 4, 6, 8
(how the type approaches the world and interacts with people):
Compliant (weakened Mind center): 1, 2, 6
Assertive (weakened Heart center): 3, 7, 8
Withdrawn (weakened Gut center): 4, 5, 9
The complements would be as follows.
Emotionally Reactive with Positive:
Positive with Competent:"(...) Emotional Realness types are probably best at working through their emotions as well as those expressed by others. It is just a matter of not over doing it, of being aware of how venting your own frustrations can significantly impact others."
Competent with Emotionally Reactive:"One problem with the Postive Outlook types is that sometimes they can easily overlook the problem, even denying its existence. The focus on happiness and positivity can be used as avoidance of problems and so it’s important for people who react like this to acknowledge that can be good sometimes to face an obstacle as it is, working through the pain and difficulty with resilience."
Withdrawn with Assertive:"The advice for the Competency group is that feelings, though messy and irrational, are necessary part of reacting to problems. Dealing with them, instead of denying or repressing, not only provides cathartic experience but also increases our empathetic connection with others, bettering relationships with all people."
Assertive with Compliant:"Types of the Withdrawn Stance can all benefit from moving themselves into the world and really being present within it. Often the types can develop great skills and talents in their time by themselves but do not ever present these to the world, focusing rather on keeping it all to themselves. It is good to learn that using these skills and showing them to the world can be as rewarding as developing."
Compliant with Withdrawn:"The general advice for the Assertive Stance types is to be aware of the other people. The types can often act without thinking about how their actions are affecting people, sometimes with very negative consequences. It the simple notion of thinking before acting but also thinking about others before doing."
"For the Compliant Stance, sometimes its good to look inward at their own desires. Each type can be self-sacrificing in some way and so to be aware of how your own desires may not be in line with your society’s desires is important in acting in a way that can attend to both."
As you can see, each tendency is looking for something else; in that manner, there is no symmetric and mutual attraction in the "Duality" sense, similar to the instinctual stacking matches. Even so, I still found this issue of Enneagram core type compatibility worthy of extra exploration and refinement.
Consequently, I went ahead and combined my findings with the types, and this was the result:
1's most beneficial type being 4.
2's most beneficial type being 5.
3's most beneficial type being 6.
4's most beneficial type being 7.
5's most beneficial type being 8.
6's most beneficial type being 9.
7's most beneficial type being 1.
8's most beneficial type being 2.
9's most beneficial type being 3.
You may say that looks fine, or you are like me and find that this overview does not truly reflect reality well enough. For instance, I cannot see all 1s gaining the most benefit from a relationship with a Type 4, or all 3s benefitting the most from being with a Type 6 etc. Mainly because those types are their disintegration points, which not all individuals of that particular Type would benefit from.
I kept thinking about this issue, and came to the conclusion that Tritype matters.
I discovered an intriguing "Enneagram/Tritype dual" connection in several long-term married couples, including my own parents (my mother is the "Enneagram/Tritype Dual" of my father), which lead me to believe that I was more unto something with including the Tritype.
So it looks like your "Enneagram Dual", the Enneagram core type you'd benefit from the most, is the opposite/complementary pole to your Enneagram Tritype's main orientation.
Each Tritype (e.g 125) has either one or two main orientations (here: Competent and Compliant) or none (meaning, they are Balanced), and its corresponding "Enneagram Dual" is the core type that is its complement (here: Type 4, who is Emotionally Reactive and Withdrawn). So if I knew someone who was 125 and they asked me what their "Enneagram Dual" was, I'd say Type 4. The order of the types in the tritype do not matter; the same would apply to 215 and 512 etc. The wing of the "Enneagram Dual" does not matter, either: here, their "Enneagram Dual" would be either 4w3 or 4w5.
Whether you will be strongly attracted to your "Enneagram Dual" or not depends on which Enneagram type(s) your Imago has. Just like you may not be that attracted to your Dual if they do not fit your Imago well enough – that does not mean that your Dual is not the most compatible with your personality type. On the other hand, just because you are in a relationship with someone who is your Enneagram Dual, or you are theirs, does not mean the union will be secured for eternity either. Having said that, one partner being the "Enneagram Dual" creates a special "glue" in relationships, which tends to keep partners together and attracted to each other for longer and better. Consider yourself lucky if you have found yourself in a good relationship with your "Enneagram Dual".
Finally, here are the "Enneagram Duals" for each Tritype:
125 (The Mentor): Type 4
126 (The Supporter): Type 4, 5, 9
127 (The Teacher): Type 5
135 (The Technical Expert): Type 4, 6, 8
136 (The Taskmaster): Type 4
137 (The Systems Builder): Type 6
145 (The Researcher): Type 8
146 (The Philosopher): Type 9
147 (The Visionary): Any Type
258 (The Strategist): Any Type
259 (The Problem Solver): Type 3
268 (The Rescuer): Type 9
269 (The Good Samaritan): Type 5
278 (The Free Spirit): Type 1
279 (The Peacemaker): Type 1, 3, 5
358 (The Solution Master): Type 6
359 (The Thinker): Type 8
368 (The Justice Fighter): Type 2
369 (The Mediator): Any Type
378 (The Mover & Shaker): Type 1, 2, 6
379 (The Ambassador): Type 1
458 (The Scholar): Type 7
459 (The Contemplative): Type 3, 7, 8
468 (The Truth Teller): Type 2, 7, 9
469 (The Seeker): Type 7
478 (The Messenger): Type 2
479 (The Gentle Spirit): Type 3
So yes, if you are for example the 147 Tritype, then every Enneagram type could be your "Enneagram Dual". Or rather, because of the inherent balance in your personality, there is no need for you to benefit from or have a preference for a specific Enneagram type.
Note: Based on my observations, the crucial aspects in Enneagram compatibility are (besides health): instinctual stackings and sharing at least one type in the Tritype (e.g 496 with 631). (Following that, the "Enneagram Dual" is just the icing on the cake.) There hasn't been a long term couple to my knowledge that has NOT shared a type in their tritype; and whenever they claimed they did not, I discovered one of the individuals was mistyped. Psychological studies usually conclude that Similarity is very important when it comes to people matching up; similarity in attractiveness, in background, in values, and so forth. Sharing one type in the Tritype creates an added sense of Similarity. People who share one type in the tritype usually have more similar interests, goals, and even childhoods or upbringings.
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