The lines of the Enneagram actually indicate the directions that each type will “travel” toward as they experience prolonged states of stress or growth.
These are called the Directions of Integration and Dysfunction, and these also provide remarkable insight into one’s type and the many ways in which we are unable to see the obvious patterns that our behavior and ego follow.
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Even in daily interactions, you will be able to see how a stressed-out, frustrated 5 can “throw up her hands” and act like an out-of-power 7; or how a very supported, peaceful 9 can begin to show signs of healthy 3-ness.
Stress vs. Growth: Directions of Integration & Dysfunction
In the above Enneagram, these directional arrows illustrate the Direction of Dysfunction, or Stress. Find your core Type on the outside, and from there, follow the arrow to see which Type your core Type resembles when under extreme or prolonged periods of stress. For example, a healthy Five may, under stress, move toward Seven--meaning he or she exhibits some of the same qualities that unhealthy Sevens do.
In THIS Enneagram, note that the arrows are pointing different directions than in the previous image. This illustrates the Directions of Integration, or Growth.
Again, find your core Type, and then follow the arrow to discover which Type you share positive, growth-oriented qualities with. Consequently, a healthy Five, as he or she becomes more self-actualized and learns to let go of some of his or her ego-dramas, he or she will begin to resemble the qualities that are admirable in healthy Eights.