The traditional, idealized picture of science looks like this:
Let’s start with a theory about how the world works. From this
theory we deduce,
using our best logic, a hypothesis, a guess, regarding what we
find in the world of our senses, moving from the general to the
This is rationalism. Then, when we observe what happens in the
of our senses, we take that information and inductively support
alter our theory, moving from the specific to the general. This
empiricism. And then we start again around the circle. So
combines empiricism and rationalism into a cycle of progressive
Now notice some of the problems science runs into: If my theory is true then my hypothesis will be supported by observation and/or experiment. But notice: If my hypothesis is supported that does not mean that my theory is true. It just means that my theory is not necessarily wrong! On the other hand, if my hypothesis is not supported, that does in fact mean that my theory is wrong (assuming everything else is right and proper). So, in science, we never have a theory we can say is unequivocally true. We only have theories that have stood the test of time. They haven’t been shown to be false... yet!
This is one of the things that most people don’t seem to understand about science. For example, people who prefer creationism over evolution will say that, since evolution is “only a theory,” then creationism is just as legitimate. But evolution has been tested again and again and again, and the observations scientists have made since Darwin have held up tremendously well. It's like saying that a thoroughbred race horse is "just a horse," and therefore any old nag is just as good!
On the other hand, creationism fails quickly and easily. Carbon dating shows that the world is far older than creationists suggest. There are fossils of species that no longer exist. There is a notable lack of fossils of human beings during the dinosaur age. There are intermediate fossils that show connections between species. There are examples of species changing right before our eyes. There is a vast body of related knowledge concerning genetics. But with every piece of evidence shown to the creationists, they respond with what the logicians call an ad hoc argument.
An ad hoc argument is one that is created after the fact, in an attempt to deal with an unforeseen problem, instead of being a part of the theory from the beginning. So, if there is a rock that is too old, or a fossil that shouldn’t be, the creationist might respond with “well, God put that there in order to test our faith,” or “the days in Genesis were actually millions of years long” or “mysterious are the ways of the Lord.” Obviously, creationism is based on faith, not science.
Science is always a work in progress. No one believes in evolution, or the theory of relativity, or the laws of thermodynamics, the same way that someone believes in God, angels, or the Bible. Rather, we accept evolution (etc.) as the best explanation available for now, the one that has the best reasoning working for it, the one that fits best with the evidence we have. Science is not a matter of faith.
Science is, of course, embedded in society and influenced by culture and, like any human endeavor, it can be warped by greed and pride and simple incompetence. Scientists may be corrupt, scientific organizations may be dominated by some special interest group or another, experimental results may be falsified, studies may be poorly constructed, scientific results may be used to support bad policy decisions, and on and on. But science is really just this method of gaining knowledge - not knowledge we can necessarily be certain about, but knowledge that we can rely upon and use with some confidence. For all the negatives, it has been the most successful method we have tried.
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
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.
Phenomenology is the careful and complete study of phenomena, and is basically the invention of the philosopher Edmund Husserl. Phenomena are the contents of consciousness, the things, qualities, relationships, events, thoughts, images, memories, fantasies, feelings, acts, and so on, which we experience. Phenomenology is an attempt to allow these experiences to speak to us, to reveal themselves to us, so we might describe them in as unbiased a fashion as possible.
If you've been studying experimental psychology, this might seem like another way of talking about objectivity. In experimental psychology, as in science generally, we try to get rid of our nasty subjectivity and see things as they truly are. But the phenomenologist would suggest that you can't get rid of subjectivity, no matter how hard you try. The very attempt to be scientific means approaching things from a certain viewpoint - the scientific viewpoint. You can't get rid of subjectivity because it isn't something separate from objectivity at all.
Most of modern philosophy, including the philosophy of science, is dualistic. This means that it separates the world into two parts, the objective part, usually conceived of as material, and the subjective part, consciousness. Our experiences are then the interaction of this objective and subjective part. Modern science has added to this by emphasizing the objective, material part, and de-emphasizing the subjective part. Some call consciousness an "epiphenomenon," meaning an unimportant by-product of brain chemistry and other material processes, something that is, at best, a nuisance. Others, such as B. F. Skinner, see consciousness as nothing at all.
Phenomenologists suggest that this is a mistake. Everything the scientist deals with comes "through" consciousness. Everything we experience is colored by "the subjective." But a better way to put it is that there is no experience that does not involve both something which is experienced, and something which is experiencing. This idea is called intentionality.
So phenomenology asks us to let whatever we are studying - whether it be a thing out there, or a feeling or thought inside us, or another person, or human existence itself - to reveal itself to us. We can do this by being open to the experience, by not denying what is there because it doesn't fit our philosophy or psychological theory or religious beliefs. It especially asks us to bracket or put aside the question of the objective reality of an experience - what it "really" is. Although what we study is always likely to be more than what we experience, it is not something other than what we experience.
Phenomenology is also an interpersonal undertaking. While experimental psychology may use a group of subjects so that the subjectivity can be removed from their experiences statistically, phenomenology may use a group of co-researchers so that their perspectives can be added together to form a fuller, richer understanding of the phenomenon. This is called intersubjectivity.
This method, and adaptations of this method, have been used to study different emotions, psychopathologies, things like separation, loneliness, and solidarity, the artistic experience, the religious experience, silence and speech, perception and behavior, and so on. It has also been used to study human existence itself, most notably by Martin Heidegger and Jean-Paul Sartre.Beware!