Perhaps more importantly, it's unfalsifiable, untestable. There's no possibility of identifying a person who is neither introverted or extraverted.

This is like having a theory that people are either short or tall, and then trying to determine shortness vs tallness by having people take surveys about whether they are comfortable in airline seats or have trouble reaching items on the top shelf. Of course everyone will fall into a little of both categories, but mostly all you are doing is wasting time.

So from a statistical standpoint, you're estimating theta, some parameter that indicates your level of extroversion. What does this parameter get you? Will you then predict this person's success in life? Why would you want to do that?

Much worse, could you possibly point to this untestable parameter as being the _cause_ of one's success? Hardly.

But from an epistemological standpoint, there is some benefit to identifying what we take to mean intro/extroversion. So that's why we give Jung credit, but more as a philosopher and less as a scientist.

The other traits aren't meaningless either, though I think their naming can be a little misleading. For example, always keeping deadlines or finishing prior to them is a high indicator of someone being a J. Ss tend to be more detail oriented, in-the-moment people, why Ns see the big picture, etc. I think if you spend some time really understanding the MBTI it can be of great help in dealing with people that are different than you.

So what I'm really trying to say - those traits don't describe how people behave, but how they process information and handle certain situations.

The problem is, the factors are dated (Big 5 is much better), it's polarising (black-and-white descriptions of people, rather than a gradated scale), and it's widely used by HR workers, managers, educationalists, and basically every other soft science department except psychology.

It's like people in the field are still using steam engines, while researchers are building petrol engines.

"The Myers-Briggs Type Indicator, called MBTI for short, more properly owes the bulk of its credit to the great Swiss analytical psychologist Carl Jung. In 1921, Jung published his book Psychological Types, in which he laid out all the same concepts found in the MBTI [...]"

"An American woman, Katherine Briggs, bought Jung's book and was fascinated by it. She recommended it to her married daughter, Isabel Briggs Myers, who had a degree in political science. The two of them got hooked on the idea of psychological metrics. Together they sat down and codified their own interpretation of Carl Jung, making a few important changes of their own. Jung had everyone fitting into one of four basic buckets. Myers and Briggs decided that each person probably combined elements, so they modified Jung's system and made it a little more complex, ending up with four dichotomies, like binary switches. Any combination of the four switches is allowed, and Myers and Briggs reasoned that just about every personality type could be well described by one of the sixteen possible ways for those switches to be set. Basically, according to Myers and Briggs, we're all represented by a four-digit binary number."

Usually, people think that extroverts are social and outgoing, while introverts are shy loners.

But that's not how Jung saw them.

For Jung, introversion was a tendency to focus inwards (think daydreamers, people with a rich fantasy life, someone form whom ideas are important).

Conversely, for extroverts the outer world is more significant than their inner world. It's just a matter of different focus or emphasis.

So, you could very well be an extrovert and be a loner. Focusing outwards, on (for instance) a personal project or (another example) exploring the external world alone.

Or you could be an introvert and be quite comfortable in social situations, and not the least bit shy, but at the same time have a rich fantasy life.

"[Neuroticism] is an enduring tendency to experience negative emotional states. Individuals who score high on neuroticism are more likely than the average to experience such feelings as anxiety, anger, guilt, and depressed mood.[1] They respond more poorly to environmental stress, and are more likely to interpret ordinary situations as threatening, and minor frustrations as hopelessly difficult. They are often self-conscious and shy, and they may have trouble controlling urges and delaying gratification. Neuroticism is associated with low emotional intelligence, which involves emotional regulation, motivation, and interpersonal skills.[2] It is also a risk factor for "internalizing" mental disorders such as phobia, depression, panic disorder, and other anxiety disorders (traditionally called neuroses)."