Personality Theories:  An Introduction

Dr. C. George Boeree

In Spanish: Teorías de la personalidad: una introducción (translated by Laura Mancini)

Personality psychology, also known as personology, is the study of the person, that is, the whole human individual.  Most people, when they think of personality, are actually thinking of personality differences - types and traits and the like.  This is certainly an important part of personality psychology, since one of the characteristics of persons is that they can differ from each other quite a bit.  But the main part of personality psychology addresses the broader issue of "what is it to be a person."

Personality psychologists view their field of study as being at the top (of course) of a pyramid of other fields in psychology, each more detailed and precise than the ones above.  Practically speaking, that means that personality psychologists must take into consideration biology (especially neurology), evolution and genetics, sensation and perception, motivation and emotion, learning and memory, developmental psychology, psychopathology, psychotherapy, and whatever else might fall between the cracks.

Since this is quite an undertaking, personality psychology may also be seen as the least scientific (and most philosophical) field in psychology.  It is for this reason that most personality courses in colleges still teach the field in terms of theories.  We have dozens and dozens of theories, each emphasizing different aspects of personhood, using different methods, sometimes agreeing with other theories, sometimes disagreeing.

Like all psychologists - and all scientists - personality psychologists yearn for a unified theory, one we can all agree on, one that is firmly rooted in solid scientific evidence.  Unfortunately, that is easier said then done.  People are very hard to study.  We are looking at an enormously complicated organism (one with "mind," whatever that is), embedded in not only a physical environment, but in a social one made up of more of these enormously complicated organisms.  Too much is going on for us to easily simplify the situation without making it totally meaningless by doing so!

We need to take a look at the various research methods available to us as personality psychologists to understand where we stand...

There are two broad classes of research methods: quantitative and qualitative.  Quantitative methods involve measurements and qualitative methods don't.  Measurement is very important to science because scientists want to get beyond the purely subjective and to the more objective.  If my dear wife and I are both looking at a man and I say "he's short," she may say "no, he's not - he's quite tall!" we are stuck with two subjective opinions.  If we take out a tape measure, we can together measure the man to discover that he is, in fact, 5 foot 8 inches.  Since I am 6 foot 2, I might think of him as short.  My wife is 5 foot 2, and she might see him as tall.  But there will be no argument about what the measuring tape says!

(Actually, there won't be any arguing in any case, since my wife is clearly always correct.)

A patch of color may seem blue to me and green to you.  A piece of music may seem fast to me and slow to you.  A person might seem shy to me and outgoing to you.  But if we measure the wavelength of color, or the rhythm of the music, or find a way to give a number to shyness-outgoingness, we can agree.  We become "objective."  Creating personality tests to measure personality traits is a common activity of personality psychologists.

If you take two different forms of measurement - such as a measuring tape and a weight scale - and we measure the height and weight of a few hundred of our nearest and dearest friends, we can examine whether the two measures relate to each other somehow.  This is called correlation.  And, as you might expect, people's heights and weights do tend to correlate:  The taller you are, generally speaking the heavier you are.  Of course, there will be some folks who are tall but quite light and some who are short but quite heavy, and lots of variation in between, but there will indeed be a modest, but significant, correlation.

You might be able to do the same thing with something involving personality.  For example, you might want to see if people who are shy are also more intelligent than people who are outgoing.  So develop a way to measure shyness-outgoingness and a way to measure intelligence (an IQ test!), and measure a few thousand people.  Compare the measures and see if they correlate.  In the case of this example, you would likely find little correlation, despite our stereotypes.  Correlation is a popular technique in psychology, including personality.

What correlation can't help you with is finding what causes what.  Does height somehow cause weight?  Or is it the other way around?  Does being shy cause you to be smarter, or does being smarter cause you to be shy?  You can't say.  It could be one way or the other, or in fact there could be some other variable that is the cause of both.

That's where experimentation comes in.  Experiments are the "gold standard" of science, and all of us personality psychologists wish we had an easier time doing them.  In the prototypical experiment, we actually manipulate one of the variables (the independent one) and then measure a second variable (the dependent one).

So, for example, you can measure the degree of rotation of the volume knob on your radio, and then measure the actually volume of the music that comes out of the speakers.  What you would find, obviously, is that the further you turn the knob, the louder the volume.  They correlate, but this time, because the knob was actually manipulated (literally in this case) and the volume measured after, you know that the rotation of the knob is in some way a cause of the volume.

Taking this idea into the world of personality, we could show people scary movies that have been rated as to how scary they are.  Then we could measure their anxiety (with an instrument that measures how sweaty our hands get, for example, or with a simple test where we ask them to rate how frightened they are).  Then we can see if they correlate.  And, of course, they would to some degree.  Plus we now know that the scarier the movie, the more scared we get.  A breakthrough in psychological science!

There are several things that make measurement, correlation, and experiments difficult for personality psychologists.  First, it isn't always easy to measure the kinds of things we are interested in in any meaningful way.  Even the examples of shyness-easygoingness and intelligence and anxiety are iffy at best.  How well do people recognize their own anxiety?  How well does a sweat-test relate to anxiety?  Can a paper-and-pencil test really tell you if you are smart or shy?

When we get to some of the most important ideas in personality - ideas like consciousness, anger, love, motivations, neurosis - the problem looks at present to be insurmountable.

Another difficulty is the problem of control.  In experiments, especially, you need to control all the irrelevant variables in order to see whether the independent variable actually affects the dependent variable.  But there are millions of variables impacting us at every moment.  Even our whole history as a person is right there, influencing the outcome.  No sterile lab will ever control those!

Even if you could control many of the variables - the psychological version of a sterile lab - could you now generalize beyond that situation?  People act differently in a lab than at home.  They act differently when they are being observed than when they do in private.  Experiments are actually social situations, and they are different from other social situations.  Realism might be the answer, but how does one accomplish realism at the same time as one keeps control?

Then there's the problem of samples.  If a chemist works with a certain rock, he or she can be pretty confident that other samples of the same rock will respond similarly to any chemicals applied.  Even a biologist observing a rat can feel pretty comfortable that this rat is similar to most rats (although that has been debated!).  This is certainly not true for people.

In psychology, we often use college freshmen as subjects for our research.  They are convenient - easily available, easy to coax into participation (with promises of "points"), passive, docile....  But whatever results you get with college freshmen, can you generalize them to people in factories?  to people on the other side of the world?  to people 100 years ago or 100 years in the future?  Can you even generalize to college seniors?  This problem transcends the issues for quantitative methods to qualitative methods as well.

What about qualitative methods, then?  Qualitative methods basically involve careful observation of people, followed by careful description, followed by careful analysis.  The problem with qualitative methods is clear:  How can we be certain that the researcher is indeed being careful?  Or, indeed, that the researcher is even being honest?  Only by replicating the studies.

There are as many qualitative methods as there are quantitative methods.  In some, the researcher actually introspects - looks into his own experiences - for evidence.  This sounds weak, but in fact it is ultimately the only way for a researcher to directly access the kinds of things that go on in the privacy of his or her own mind!  This method is common among existential psychologists.

Other researchers observe people "in the wild," sort of like ethologists watch birds or chimps or lions, and describe their behavior.  The good thing here is that it is certainly easier to replicate observations than introspections.  Anthropologists typically rely on this method, as do many sociologists.

One of the most common qualitative method in personality is the interview.  We ask questions, sometimes prearranged ones, sometimes by the seat of our pants, of a variety of people who have had a certain experience (such as being abducted by a UFO) or fall into a certain category (such as being diagnosed as having schizophrenia).  The case study is a version of this that focusses on gaining a rather complete understanding of a single individual, and is the basis for a great deal of personality theory.

Ultimately, science is just careful observation plus careful thinking.  So we personality psychologists do the best we can with our research methods.  That does leave us to consider the business of careful thinking, though, and there are a couple of particulars there to consider as well.

First, we must always be on guard against ethnocentrism.  Ethnocentrism is (for our purposes) the tendency we all have to see things from the perspective of our own culture.  We are born into our culture, and most of us never truly leave it.  We learn it so young and so thoroughly that it becomes "second nature."

Freud, for example, was born in 1856 in Moravia (part of what is now the Czech Republic).  His culture - central European, German speaking, Victorian era, Jewish... - was quite different from our own (whatever that might be).  One thing his culture taught was that sex was a very bad thing, an animal thing, a sinful thing.  Masturbation was thought to lead to criminality, retardation, and mental illness.  Women who were capable of orgasms were assumed to be nymphomaniacs, unlikely to make good wives and mothers, and possibly destined for prostitution.

Freud is to be respected in that he was able to rise above his cultural attitudes about sex and suggest that sexuality - even female sexuality - was a natural (if animalistic) aspect of being human, and that repressing one's sexuality could lead to debilitating psychological disorders.  On the other hand, he didn't quite see the possibility of a new western culture - our own - wherein sexuality was not only accepted as normal but as something we should all be actively engaged in at every opportunity.

A second thing to be on guard against is egocentrism.  Again, for our purposes, we are talking about the tendency to see our experiences, our lives, as being the standard for all people.  Freud was very close to his mother.  She was 20 when she had him, while his father was 40.  She stayed home to raise him, while his father was working the usual 16 hour days of the time.  Little Freud was a child genius who could talk about adult matters by the time he was five.  He was, as his mother once put it, her "golden Siggy."

These circumstances are unusual, even for his time and place.  Yet, as he developed his theory, he took it for granted that the mother-son connection was at the center of psychology for one and all!  That, of course, was a mistake:  egocentrism.

Last, we need to be on guard against dogmatism.  A dogma is a set of ideas that the person who holds those ideas will not permit to be criticized.  Do you have evidence against my beliefs?  I don't want to hear them.  Do you notice some logical flaws in my arguments?  They are irrelevant.  Dogmas are common in the worlds of religion and politics, but they have absolutely no place in science!  Science should always be open to new evidence and criticism.  Science isn't "Truth;" it is just a movement in that general direction.  When someone claims they have "Truth," science comes to a grinding halt.

Well, sadly, Freud was guilty of dogmatism.  He became so attached to his ideas that he refused to accept disagreement from his "disciples."  (Notice the religious term here!)  Some, like Jung and Adler, would eventually go on to develop their own theories.  If only Freud had not been dogmatic, if only he had been open to new ideas and new evidence and allowed his theory to evolve openly, we might all be "Freudians" today - and "Freudian" would mean something quite different and much grander.

Enough of this beating around the bush.  Let's get started.  Where should we start?  At the beginning, of course.  And that would be the great master himself, Sigmund Freud.

© Copyright 2007, C. George Boeree