The reason why the five factors are no more than five is a pretty reason.Because they are not six?Yes, indeed: thou wouldst make a good fool#2

Here at the Riddled Blogging and Combine-Harvester Racing Club we pay little heed to requests from the readership or suggestions of targets for satire, for readers are known to be fickle and feckless and even vice versa, easily distracted by the news cycle and its ephemeral celebrities. In the particular case of Jordan Peterson, it is hard to make him look any more ridiculous or intellectually squalid than he has already managed by himself by talking to journalists.

Several years ago, Jordan Peterson told me he wanted to buy a church. This was long before he became known as “the most influential public intellectual in the Western world,” as he was described in the pages of the New York Times a few months ago. It was before he was fancied to be a truth-telling sage who inspired legions, and the author of one of the bestselling books in the world this year. He was just my colleague and friend.
I assumed that it was for a new home — there was a trend in Toronto of converting religious spaces, vacant because of their dwindling congregations, into stylish lofts — but he corrected me. He wanted to establish a church, he said, in which he would deliver sermons every Sunday.

In contrast, I am always willing to rant about the Five Factor approach to psychology, often at excessive length, which is why I am seldom invited to parties. The Five Factor Model or FFM is one of several forms of 'trait personology' allowing persons to portray their image of themselves by endorsing or rejecting a series of descriptors from a questionnaire [descriptors = adjectives or self-descriptive phrases]; their responses are variously combined to score the subject on five broad scales. Their names are sometimes abbreviated to OCEAN, because NEOCA sounds like it could be a cellphone manufacturer. You might encounter the system in Vocational Astrology, used to determine your shape as a peg, in order to drive you into the appropriately-shaped hole... in this context, scores on Conscientiousness and Openness (say) are found to be more rigorous and plausible than the language of "Venus in trine, Moon in the Fourth House, Jupiter in Opposition". The big question is how much you can predict about someone if you know their score on (for instance) Neuroticism (other than their score on some future Neuroticism test), and the answer is "two-thirds of sweet fuck-all".
The general rule with trait psychology is that its insights can be right, or non-trivial, but not both, and the FFM is not glaringly wrong. It is not as fraudulent as some rival tools for psychometric astrology, for it is distantly related to observations and supported by a fragile scaffolding of circular reasoning and evidence collection; as opposed to (for instance) the Myers-Briggs system, which is rectally-sourced in its entirety.

Much of that fragile scaffolding involves Factor Analysis in some way. FA is well-favoured in numerically-inclined schools of psychology, and when I get around to writing my long-promised textbook on "Artefacts and flaws of different numerical methods: Choosing the one that matches the desired results", it will be the first chapter. When you have taken some devoutly-wished-for conclusion and built it into the design of some questionnaire or inventory, FA is the instrument of choice for discovering that easter-egg within the test responses, while you feign an expression of gratified surprise that Objective Reality has hewed so closely to your theory. There was going to be a metaphor here about the rabbits so often discovered within top-hats, and how Objective Reality must have placed them there, but let's go with Thomas Mann instead:

It pleases me to imagine that Mann intended Pharoah's Daughter and her attendants to be an allegory on the banks of the Nile of Factor Analysis.

But this brings us back to Jordan Peterson. Peterson is in demand because he burdened himself with the demanding though well-remunerated role of Socially-Conservative Intellectual -- making garbage people comfortable in their bigotry and reassuring them that their predigested opinionations are simply recognitions of Objective Reality -- but he also has a day-job as an employment psycholomogist.* With the FFM as his specialty, which is enough to bring him into the Riddled wheelhouse after all, assuming that he can find room there among all the wheels.

Peterson has his own proprietorial variant, the "Unfakeable Five Factor" test: marketed as spoof-proof and resistant to subjects using their responses to paint a false personality picture. You can hire him as an Expert Witness, to testify to the undistorted validity of profiles thereby obtained (and in child-custody cases, to the custodial superiority and non-violence of the father). Alas, his ill-prepared forays into the realms of jurisprudence were not a great success, unless by "success" you mean "inspiring judges to criticise junk-science and unfounded self-estimation in creatively pungent phrases", and his testimony was ruled inadmissible on account of being abject bafflegab. Do readthose Rulings: the judges do not hold back on Peterson's arrogance and lack of preparation.

[19] This is perhaps the most interesting of all of the reports that counsel for the respondent wishes the court to consider.  It comes as close to “junk science” as anything that I have ever been asked to consider. 

Now I have exhausted my knowledge of the Peterson oeuvre so I shall continue by mining the comments for clever aperçus and pretending to be their author:

It was like Joseph Campbell got hit by a bus and no one noticed, and he staggered across the street to the public library with blood running down his head, and he read nineteen pages of The White Goddess, and three chapters of The Golden Bough, and then the last two-thirds of Émile Durkheim's Wikipedia page, and suddenly he understood the shape of the world beneath its shroud of falsehoods and deceits. And also he lost about 50 I.Q. points. And Peterson's fans are all so dumb they're unable to notice that not only is their Emperor naked, he's actually a horse. I don't know how that anthropomorphized clownshoe has been able to pass himself off as an intellectual for all these years.

But what I really want to say about this FFM approach is how unambitious it is. We no longer hear depth-psychology talk of mapping the mechanisms of the mind in order to predict cognition and behaviour [this paragraph sounds better if you imagine Vincent Price reading it out in his most sententious tones]. Instead we have learned a lot about the folk-psychology narratives and conventions and expectations that we use to make sense of people's behaviour, for now that psychology is all about measuring impressions of personality -- outsourcing the work to untrained observers and tabulating their responses, though without any diminution of professional prestige or remuneration -- it has become a study of the limitations of observers. Depth psychology has drained out to the approximate superficiality of an oil-slick on a wet road. It is like when you lose your keys in a territory so you search for it on a map because there is more light there.

That analogy needs work, so here is another one. We see three dimensions of colour. This is a perceptual limitation rather than a feature of the ambient environment -- evolution has no time for the full complexity of spectral variations among different light sources, and our eyes and brains are designed to throw most of the information away (colour space is only two-dimensional for most mammals; birds routinely have four or five dimensions of colour experience). Were someone to conclude from our perceptual incapacity that the manifold of spectral variation is only three-dimensional in physical reality, we would view that person as very silly indeed, or else a Five-Factor theorist.

A closing paragraph should go here but I can't be arsed writing one right now. Maybe tomorrow.

* What is it with Occupational Psychologists? That was originally Dr Linda Gottfredson's area... though rather than using the FFM to measure pegs and match them to vocational holes, she specialised in Holland's aptitude schema, which has six factors rather than five, arranged in a hexagonal circumplex (in turn, Holland's RIASEC scheme should not be confused with the Hogan Personality Inventory, which has six or possibly seven factors, and is popular in executive-headhunting circles). The whole field is roughly on a par with phrenology in terms of intellectual rigour, but at least it helps the practitioners find gainful employment, if no-one else. At some point, though, Gottfredson took a sharp turn into white-supremacy thinking, swallowed 'The Bell Curve' holus-bolus, and was the main instigator (along with fellow-sewer-rat David Brooks) of an Open Letter / full-page advertisement in the WSJ, supporting its message of 'race realism'.