Enneagram Personality Theory
A research-oriented overview and critique of the Enneagram as a personality model.
The Enneagram can have descriptive value as a system of nine personality types, but many of the broader claims attached to the system are difficult to justify scientifically. The strongest case for the Enneagram is therefore the simplest one: nine recurring personality descriptions that may help organize recognizable differences between people.
Origins and Development
The modern Enneagram appears to draw from a mixture of older religious, philosophical, and mystical traditions, including ideas associated with the Seven Deadly Sins, Kabbalah, Sufism, the Chaldean tradition, and Gnosticism. Much of this material originated in periods when personality theory was based more heavily on intuition than on systematic psychological research.
Claudio Naranjo played a major role in adapting and popularizing the personality-oriented version of the Enneagram in the West. Many later Enneagram authors and schools developed their systems from ideas influenced by his work.
The Nine Types
As a nine-trait personality system, I think the Enneagram has real descriptive value. Any personality model containing sufficiently distinct and recognizable traits can potentially be useful for describing differences between people.
The difficulty is that Enneagram type descriptions vary from author to author. Without a clearly specified underlying measurement model, deciding which version of a type description is most accurate becomes difficult. There are also overlap and orthogonality problems: some Enneagram types correlate with one another rather than behaving as clearly independent dimensions.
The Enneagram Symbol and Type Relationships
The larger theoretical structure is more questionable. The claim that the nine personality types have specific psychological relationships corresponding to the connections drawn on the geometric Enneagram symbol has not, in my research, been supported by convincing empirical evidence.
Likewise, the ordering of the nine types around the Enneagram circle does not appear to correspond consistently with the way the traits correlate statistically. If the underlying ordering is not supported, theories that depend on neighboring positions become much harder to justify.
Wings
Wing theory assumes that the types immediately adjacent to a person's main type have a special influence on personality. I have not found the statistical relationships among the types to support that assumption. For that reason, I have moved toward emphasizing a person's main type rather than treating wings as a necessary part of Enneagram interpretation.
Instinctual Variants
Instinctual variants are intended to explain meaningful differences between people who share the same primary Enneagram type. The idea may be descriptively useful, but variant definitions remain relatively inconsistent across Enneagram literature.
This creates the same fundamental problem found with the primary types: without a coherent empirical structure and agreed-upon measurement criteria, disagreements between descriptions are difficult to resolve objectively.
Scientific Limitations
My main criticism of the Enneagram is not that its personality descriptions are useless. It is that many claims surrounding the system extend considerably beyond what has been demonstrated empirically.
Personality theories become more useful when their claims can be defined clearly, measured reliably, compared against alternatives, and reproduced in independent data. The Enneagram's future value as a psychological model depends on separating useful descriptive traits from claims that are primarily traditional, symbolic, or speculative.
Recommended Enneagram Books
For people interested in the historical and theoretical development of the Enneagram, I would start with:
- Claudio Naranjo — Character and Neurosis
Of the major Enneagram books, this is the one I consider closest to a psychologically oriented treatment. - Helen Palmer — The Enneagram
A well-known presentation of the nine-type system and its traditional interpretations. - Don Richard Riso and Russ Hudson — The Wisdom of the Enneagram
An influential and widely used presentation of modern Enneagram theory.
Bottom Line
Personality types are not necessarily tied to the validity of the larger system that produced them. Even if parts of traditional Enneagram theory are unsupported or poorly structured, the nine type descriptions can still contribute useful ideas to the broader study of personality.
The most productive approach is to treat those descriptions as hypotheses about personality structure and evaluate them empirically rather than assuming that the complete traditional Enneagram framework must be correct.