What is Intelligence?

There is no definitive answer to the question, "What is Intelligence?" In fact, there are almost as many definitions of intelligence as there are dictionaries. One thing most definitions share is an emphasis on mental ability or capacity. Consider the following definitions.

The capacity to acquire and apply knowledge.

The faculty of thought and reason.

The ability to think abstractly as measured by objective criteria.

The skilled use of reason.

Only the last one refers to intelligence as applied brainpower. It does not say "the ability to reason," but "the skilled use of reason." But this still might refer to how well one manipulates words without implying that the user is smart in applying that brainpower to real life situations. That brings us to some other definitions:

The ability to comprehend; to understand and profit from experience.

The ability to learn or understand or to deal with new or trying situations.

These are still about abilities rather than proven tendencies or habits of acting intelligently, but also mention profiting from experience and dealing with new situations. That starts to get towards a definition of functional or applied intelligence. Of course we can't define it in a way that accounts only for "street smarts." There are people who have no common sense in everyday life, yet can clearly outthink most of us. We need some way to refer to this measurement of raw capacity, and the word "intelligence" is what we have.

In any case, the purpose of this page is to raise questions rather than to claim definitive answers. For example, should we call a man intelligent if his big smart brain only results in stupid actions? Then there is the following question:

What is Intelligence As Measured by IQ Scores?

Most of us feel comfortable judging one person to be more intelligent than another, especially when the difference is significant. This judgment about the relative brainpower of various people is measurement in its crudest form, and so we inherently believe in our ability to measure intelligence, even if we may argue about how precise we can in doing so. We might at least say of intelligence that we know it when we see it.

But we can also recognize that an IQ test (or any other) only measures certain mental abilities, and it would be naive to think that we can reduce intelligence to just those areas of mental activity. IQ tests look at several different types of mental processes, such as verbal capacity, perceptual organization, short term memory, spatial visualization, and perceptual speed. But we know there is more to good thinking than just what shows up on a test.

For example, most of us can agree that knowing how to comfort a friend or to negotiate the best deal on a car are signs of intelligence, yet these skills are rarely tested. And though they are learned skills to some extent, that is not the whole story. We know from experience that some of us are born with more ability to relate to others, for example, or to sell things and ideas (we say a man is a natural born salesman, and there is an element of truth in the idea).

In 1983 Howard Gardner proposed that there are numerous types of intelligence. He listed seven, later expanded to nine. They included; Spatial, Linguistic, Logical-mathematical, Kinesthetic, Musical, Interpersonal, and Intrapersonal. He argued that the traditional view of intelligence doesn't address the wide variety of abilities humans have.

Critics say his ideas are non-scientific, have never been tested and never subjected to peer review. Perhaps, but they do point out the fact that what we choose to test is somewhat arbitrary and incomplete. Critics also claim that the types of intelligence he points to are indicative of more basic faculties that are (or can be) tested. For example, perhaps reasoning skills could explain interpersonal abilities. But this seems unlikely. What part of a standard IQ test consistently indicates the likelihood that the test-taker will know what to do when he has a problem with a neighbor? The ability to find a peaceful resolution to a problem with another person is a mental process, a part of intelligence, and clearly some people are innately better at it than others.

In addition to the arbitrary nature of deciding what is a part of intelligence and what isn't, there is another problem that makes any pretense of accurate measurement seem questionable at best. It is the designation of relative values to the various parts of a test. For example, should a question that tests verbal ability be assigned the same value in the figuring of the final score as one that addresses mathematical ability? There is no objective answer.

We might posit all sorts of ways to assign values. For example, we might research which tested abilities are more likely to lead to success in life, and then weigh the various elements accordingly. Of course,in that case would have to answer the question of what success is. We might start with the idea that we know intelligence when we see it, and have researchers or random people rate intelligence in subjects, then look at those subjects who were rated most highly to see which abilities they are strongest in. A test would then be designed based on giving more weight to those capacities.

All of the ways in which we might weigh the elements are arbitrary to a large degree. Imagine two test-takers, one who scores high in all areas except verbal abilities, and one who scores high in verbal abilities and scores about the same as an orangutan in all other areas of the test. The second might very well appear to be more intelligent, since he can communicate better. He may even be more likely to succeed in the various endeavors of life? But on most tests the first person will have the higher IQ score.

Suppose a man could score at genius level if he had unlimited time to take an IQ test, but actually scores very low because he is very slow. Is he really less intelligent than a man who can answer fewer questions but does so more quickly? Even if we allow that speed of thought is an element of intelligence, how much weight should it be given? Again, it is clear that there is not an objective standard that all would agree to.

What is intelligence? We might say it is the set of abilities measured by an IQ test, but that is not a very satisfying answer. The concept predates the tests, after all, and there is more than one test, and the choice of which elements to measure - or not to measure - is always somewhat arbitrary.

There is another interesting question here: Can we - or should we - separate the way in which we measure and define intelligence from the reasons for doing so? In other words, in deciding what it is or how to measure it, should we start with the question of why we want to.

Why do we want to assign a number to a person's mental abilities? If it is to give us some way to predict what he might be best suited for academically or in the world of employment or business, might we be better off just measuring those abilities more directly? Whether a man would make a good judge or a good engineer, for example, might have little relation to an IQ score, but could be presumably tested more meaningfully with a test involving judging or answering engineering questions.

I have to admit that I do not know what wonderful and useful purposes IQ scores have been put to. I haven't researched this matter. I suppose a score could at least provide a base, so future testing would show if certain mental abilities were declining, which might suggest health problems. And a score of 60 versus 160 certainly can mean something in terms of whether a person can handle a given mental task. On the other hand, is there a real value in knowing whether a man has a score of 110 or 140? Perhaps we should drop the illusion of accuracy and limit scores to "below average," "average," and "above average."

It may be that we are too ambitious in even positing the concept of intelligence as one "thing" that can be measured or understood as a whole of its parts. It might make more sense to say, "he knows how to express himself very well," and "she really knows how to crunch the numbers," and "he is very good at visualizing," and leave it at that. Certainly we are smarter in some areas than others, so why not address these directly without the necessity to "add them up" into "intelligent," "more intelligent" or a score that may not really provide much useful information?

What is intelligence? We may know it when we see it - or then again, maybe not. In any case, the answer is not as definitive as we may like to think.

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