This article originally appeared on greaterlight.ca.
Although your Enneagram type is not your final destination on your inner journey, you need to start somewhere. Any ongoing work with the Enneagram presumes you have found your type accurately. This takes time and guidance from a reliable source.
The Forer Effect
A common criticism of the Enneagram of Personality is that its type descriptions are so general that the symbol cannot meaningfully distinguish between personality types. Psychologist Bertram Forer described this phenomenon, now known as the Forer effect, in a 1949 paper. Forer did not explicitly study the Enneagram (it was not widely known at the time), but some critics of the Enneagram cite his study as evidence of its unreliability as a system of personality.
Forer made an object lesson of his introductory psychology class by having the students fill out a psychological assessment form and promising to return the results after he’d had time to examine them. He said he would give each of the 39 students a personalized “sketch” (a short written description) of their personality based on his analysis of their answers.
A week later, Forer returned the personalized analyses to the class, on the condition that each student keep their own result secret from the rest of the class. The sketches contained 13 statements such as, “You have a great need for people to like and admire you.” and “You have a great deal of unused capacity which you have not turned to your advantage.”
Forer asked the students to read their sketches and write on the back of their paper a rating of the effectiveness of the test in determining personality generally and the accuracy of their personality sketch in particular. These two factors were to be rated from 0 to 5, with 5 being the most effective or accurate. After they had rated the test instrument and sketch, Forer asked the students to mark each statement in the sketch as True, False, or Don’t Know.
Nearly all of the students (38 out of 39) rated the effectiveness of the test as 4 or 5, thus very highly effective. A large majority (34 out of 39) rated the accuracy of their own personality sketch as 4 or 5. A large number of students (28 out of 39) stated that 10 or more of the 13 statements in their sketch were true.
Forer had played a trick on his students. Every one of the 39 personality sketches was absolutely identical. The statements could have come out of a fortune cookie. In fact, they “came largely from a newsstand astrology book”. (Even astrologers don’t put much stock in newspaper astrology.) Forer revealed this to the class and used it to caution his students to be careful when evaluating someone’s claims to understand the phenomenon of personality. The students’ response was to ask for copies of the sketch so that they could try it on their friends.
Universal and Personal Validation
Forer noted in his paper:
“Virtually every psychological trait can be observed in some degree in everyone. For the purpose of characterizing a particular individual, stipulation of those traits which he demonstrates is a meaningless procedure. It is not in the presence or absence of a trait that individuals differ. […]the individual is a unique configuration of characteristics each of which can be found in everyone, but in varying degrees.”
Forer concluded that if a statement about a personality trait is general enough, chances are good that most people will think it applies to them personally. And it does, because it applies to everyone. However, Forer claims this makes it useless as a means to distinguish individuals by their personality traits. Where people err is in assuming that a statement that is universally valid (one that applies to everybody) is a statement that is personally valid (one that uniquely and accurately describes them).
Is the Enneagram subject to the Forer Effect?
Well, yes and no. It depends what you think the Enneagram is and how it has been presented to you. The real question is whether Enneagram assessment, particularly self-assessment, is subject to the Forer effect.
If you have completed a test or questionnaire that presents you with a description of a single type as an “answer” to the test, the result may well be subject to the Forer effect. Without other type descriptions to compare to, the description might plausibly sound like an accurate assessment of your personality. If an assessment tells you what your type is, as opposed to leading you to discern and verify it for yourself, treat it cautiously, as no more than a starting point for further self-inquiry.
That being said, some tests are better than others. The Riso-Hudson Enneagram Test Indicator (RHETI) and the Wagner Enneagram Personality Style Scales (WEPSS) are two that have been carefully designed and tend to give good results. Both say that you should treat the result as a starting point, not a final assessment. (I completed both tests as part of the research for this article. I found the results accurate, but I know enough about the Enneagram to see what the questions were getting at while completing the tests. I think it would be possible to game the system. Caveat emptor.)
More-complex assessments will present you with descriptions of all nine types. Well-written presentations will show you distinct differences and similarities among the types. Discerning your type accurately presumes a certain amount of self-knowledge and honesty. Unless you have done some inner work already, you may be unaware of automatic patterns in your personality that can cause you to respond inaccurately to descriptive statements about an Enneagram type.
Avoiding the Forer Effect
You can avoid the Forer effect in Enneagram work, but it’s a much longer road than a one-time test. First, you must learn the broad outlines of the system, preferably from a teacher or a good introductory book with lengthy descriptions of each type and comparisons between types.
“Try on” a type. Over a period of time, observe your reactions to life’s impacts and see if they match your proposed type’s description. Submit your observations to the discipline of a long-term spiritual practice, such as meditation or prayer.
Get honest feedback on your observations from a trusted person who knows you well. Guidance from a teacher or spiritual director is very helpful at this stage, as is work within a spiritually-oriented community.
As you continue your practice of self-observation, you may decide your type is not the one you first chose. Over time, your type will slowly come more into focus. This takes much longer than doing a one-time assessment, but will give you a much more reliable foundation for future work.
 Also known as the Barnum effect, named after P. T. Barnum, the 19th-century American circus showman. The aphorism, “There’s a sucker born every minute.” has been attributed to Barnum, probably apocryphally.
 Forer, B. R. (1949). The fallacy of personal validation: a classroom demonstration of gullibility. The Journal of Abnormal and Social Psychology, 44(1), 118-123.