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Interview with Dr. John L. Horn

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This interview took place at his home in San Pedro, California on June 28, 2004.

(1) Click here to watch Dr. Horn discuss how he became interested in the study of intelligence:

Well, Jerry Davison teaches a course [at the University of Southern California ] in which he has people come in and talk to his class about how they happened to get into psychology. And one of the things he noted to me one day is that he gets the same person in in successive years, or in different years—He noticed that the same person in different years gave quite different stories. [laughing] And his explanation for that—Jerry Davison is a clinical psychologist—was that it kind of depends on where you are in your life now how you if you think you got into it. So, I don't know that I can be fairly accurate on this, but, I majored—When I went to university I majored in mathematics and chemistry. My idea was that well maybe, just maybe, if I got through the university I could get a job teaching in high school. I could teach mathematics and chemistry. Well, along about my third year—I loved psychology. I just loved reading about it. I was—I thought of myself kind of a crazy individual and psychology studied crazy individuals, so I was interested in studying crazy individuals. I mentioned that I liked Piaget's work [previously in this interview]. I very much his theory of games, for example. Children's games, and so on. And just, you know, I read a lot of that stuff and I took courses in it. I had no idea that I could ever be a psychologist. Well, this professor I had said “Well John, aren't you planning on going to graduated school?” And I said “Well, I don't think so. I don't think people like me go to graduate school, do they?” He said “Oh yeah! You, you, you could—you'd be a—You'd get a scholarship to go to graduate school and study psychology.” So, that was—that was an eye opener to me. The professor was named Brown, and he had—he had said “Well, you could do that.” So I switched my major in my junior year from mathematics and chemistry to psychology, and began you know, in earnest trying to study even more psychology than I'd been studying up to that time. So, I don't know. I was—I was interested in—I was interested in writing, to tell you the truth. I thought I could maybe write the Great American Novel or something like that. And what interested me in writing, to a very considerable extent, was people. I loved biography, and I read a lot of biography as a young person. So psychology to me was like biography. It was like studying individuals and understanding people, and that's what I wanted to do was understand people. And every aspect of people. So, I wasn't just interested, for example, in abilities at all, in fact. As I said, I liked Piaget's theory of games and why children play them and how they get these ideas about what the rules of games are and I thought that most interesting in my first readings of Piaget. And so, I don't know. It sort of grew out of I guess this interest of biography and this interest in well, craziness if you will. This interest in—I really liked abnormal psychology. I wanted to kind of understand crazy people. Not-crazy people too, but crazy people were particularly interesting. As I said, I thought I was kind of crazy so I wanted to understand myself better too. I think that's why many people go into psychology—Is to try to understand themselves better. And by understanding other people better we think we can understand ourselves, I think. So I don't know. That's what I think got me into psychology. But if you ask me next year I might have a different story to tell!

(2) Click here to watch Dr. Horn discuss his professional influences:

Of course I think it comes as no news to most who know anything about me at all that Raymond Cattell would be the-- perhaps the person who most influenced me. He was just such a—such a fluent and diversified genius that it was hard—You couldn't be around him much without being influenced, let's put it that way. And of course his thinking on cognitive abilities very much influenced my thinking on cognitive abilities. And we both derived very directly from Spearman 's work, so I think I see myself as very much an outgrowth of Spearman 's thinking. Much of what I talk about as fluid ability is really what Spearman talked about as g. And then in line with that, why, I saw the discussions, the debates, that Spearman had with Cyril Burt, and then later with L.L. Thurstone and that very much—those kinds of thinkers very much affected the way I came to regard the subject, and regard the research on cognitive abilities. In that same group, if you will, McDougall I found to be extremely influential. That is, McDougall brought the ideas of motivation, and the ideas of self-regarding sentiment, and the ideas of how the abilities fit within personality, the general personality, that very much involves drive and motivation and perceptions of what is worthwhile to do and so on. So that kind of thinking was pretty much at the root of some of my ideas about crystallized abilities and how crystallized abilities come about. I had also been interested, not so much in particular individuals, as in the general topic of anthropology and the way in which the anthropologists thought about acculturation, the way they thought about they ways in which societies are distinguished by their acculturation. Those ideas very much influenced the way I came to theorize about crystallized cognitive capabilities. So in my early training at least, I think those were the primary kinds of influences.

(3) Click here to watch Dr. Horn discuss how his thinking has evolved during the course of his career:

There's quite a few things I've changed my mind about in regards to psychology—what I thought I knew, what I thought psychology was all about. But particularly in respect to cognitive abilities, I think when I first entered this study I was expecting that there was something called general intelligence, and that that developed out of early genetic determiners, and these interacting with the environmental determiners, and that we would find evidence then, for general intelligence. What I kept finding as I studied first Piaget and then Cattell and generally looking at the cognitive ability literature going back to Spearman , the studies of Cyril Burt at the early turn of the century, the work of Binet —is that the evidence simply did not point in the direction of there being a general factor of intelligence, as if there was one intelligence. And in fact, what the evidence kept coming back and saying was that there are several kinds of cognitive capabilities which you can combine in any of an infinity of ways to make what you might call a general factor. But those infinity of ways that you combine it are different. That is, they result in a different what you might call general ability, general factor, general intelligence, and there is no one of them which turns out to be, as yet, a general intelligence. So, the term “intelligence” as used in popular language and so on, is permissible I think, in that it's not unreasonable in that context, but from a scientific point of view, we do not have evidence. We have not yet found—that is, not yet—if there ever will be any indication that there is something called general intelligence. So that's probably the most fundamental thing that has changed in my—in my study of cognitive abilities—is just come more and more to realize from the evidence that what I thought initially was true, something like a general intelligence simply is not true. That's probably the most important thing that's changed. But I've changed my mind on quite a few other things too.

(4) Click here to watch Dr. Horn talk about the development of cognitive abilities:

I've changed my mind about the variety of ways in which cognitive capabilities are developed, or how they are influenced in development--how so many different factors influence the different varieties that we call cognitive capabilities—what many people refer to as intelligence. There are so many things that operate through development to make what comes out in individual differences in different people just quite different--quite different manifestations. We see it all around us of course when we look at a very skilled actor or actress for example. We look at a very outstanding scientist in say, physics, or we look at an outstanding person in literature. And you know, we just see that they--the work they're expressing as cognitive capabilities are so different, and they come from such different—such different backgrounds and such different sets of influences. To find the generality, if there were one—It would be really a very worthwhile thing to do. If we could find some thread through all of those that was, the quote, the factor that was determining outstanding performances and outstanding thinking and so on in these various different areas. But we have yet to find it. The other, I think, major change that has come about in recent years in my study of cognitive abilities is I've come to believe that much more as we go into adulthood what is manifested as cognitive capability is in domains of expertise. That is, that people move away from the kind of--in the United States, anyhow--the kind of standard educational preparation that results in a number of a kind of verbal and mathematical and fluency kinds of abilities—They move away from that into special areas of creativity and special areas of exploring the limits of their abilities, and they develop therefore very profound, very advanced kinds of—we call them intelligence, but again, very different kinds of intelligences. We'd call these different areas of expertise. And most of us, I think, are some sort of mélange, in adulthood, of different expertises. That is, we're kind of really good in maybe one or two things, really show our intelligence mostly there, and we're kind of good in some other things and we're kind of dreadful in some other things, you know. So that if you look at different individuals, you see different mixtures, different mélanges of cognitive capabilities and different abilities or different kinds of collections of their expertises.

(5) Click here to watch Dr. Horn talk about fluid and crystallized intelligence:

Well the expectation, as I said before, was that there would be a unity about cognitive capabilities. And the unity that was thought to occur was one in which there would be these genetic capabilities, and those would be met with environmental opportunities, and out of that interaction of genetic capabilities and environmental opportunities would emerge a form of intelligence. And it was discussed that what would emerge out of that would be general intelligence, and you could see that in individual differences. Well, as a matter of fact when Piaget first pointed to what he saw developing in his children for example, in cognitive capabilities—What he saw was something rather different from that. That is, there seemed to be, right from an early age, a kind of fluency kind of capability, and a capability that involved ready association of concepts with verbal tags, which resulted in kind of a brightness in verbal expressions of intelligence. And concomitant with that however, in another of his children, he saw developing a kind of quiet reasoning which did not necessarily link with the relationships between concepts and the popular language, or the language within which the child was being raised. So that the person was expressing awareness, understanding and doing things in the environment that indicated that he was—she was (it was she oftentimes) thinking analytically, but that this was not—this was going on—this kind of capability was going on separately in a sense. Not separately, but in a sense that it could be more developed in some children than in others, whereas this other could be more developed in other children then. So that right from an early age—age two and thereon—it appeared that this distinction between a fluid reasoning kind of capability and a cultural absorption kind of ability—acculturation kind of ability—was beginning to take place. So that it appeared that instead of there being like, one, as it were, set of genetic determiners giving us general intelligence, there were different sets of genetic determiners kind of pushing one direction or another. Well, that I think, that early indication of a distinction between forms of intelligence led to other observations by—as the research into what was general intelligence continued, so that we began to notice also that some people were very, as it were, visually competent, visually alert, visually able to perceive things that were not necessary thinking in this analytic was, as I mentioned earlier, not necessarily doing this kind of cognitive development that very much linked the language to the concepts. So the diversity of influences on cognitive capabilities seemed to be coming from different kinds of genetic as well as, perhaps early determiners. But different kinds of genetic factors were operating. And, so that early on Ray Cattell noticed this difference. Donald Hebb noticed this difference, that you were getting this distinction between the fluid and crystallized, and then, as I say, with a further look it seemed also that not only was it fluid and crystallized, but it was also visual, and it was also auditory distinctions that were producing these different versions, if you will, of what might be called—what might have been called intelligence. But now we had to use the plural term “intelligences” because they were coming about really quite differently. So that fluid and crystallized was like one of the early things that we observed. But as I say, we can see it in Paiget's work as well as the work that was being reviewed by, or being looked at by Hebb when he was looking at brain damage, and the work that Ray Cattell was looking at when he was looking at age differences. So there were those three perhaps major kinds of--sets of evidence that was pointing to this distinction between fluid and crystallized, and then that distinction opened up the ideas of, the distinctions of visual kinds of intelligences, and auditory kinds of intelligences and the notion, really that we I think now are working with, which is kind of multiple intelligences, or at least several forms of intelligence.

(6) Click here to watch Dr. Horn talk about crystallized intelligence and expertise:

I think the more recent work on crystallized, is as I mentioned before, if you think of intellectual capacities, or if you think of capacities for becoming cognitively capable, and then think about, well, what do those capacities come from, then—For example, look at the way in which the human brain is structured and you see that the genetic structural level—they come from different organizations of the—different emphases in organizations of the neural structures. And then if you think of the way in which these neural structures kind of would make you more and less susceptible to some kinds of environmental opportunities and influences than others—You can see that the whole process of cognitive capabilities developing over a lifetime. And now then if you come into adolescence and adulthood you see those things are still going on. You're still —You don't stop developing somehow at age 20 and realize you're at the end of your intellectual capacity. You keep on developing in adulthood, and as I was saying, the adulthood development seems in many people to be along different domains of expertise, if you will. So you kind of leave your school training behind as it were, and develop new structures, new comprehensions, new understanding. And that's the way intelligence should be measured I think—is measured, is measured well in adulthood. We're using new tasks to do it, and we use those tasks in the domains of expertise where people are to find out, to sort of describe what we see as intelligence in mid-adulthood and older adulthood. It's not to say that there won't be decline in cognitive capabilities. There very possibly will be, but I think it would be decline that we should be looking for in the domains of expertise where people are really applying their cognitive capabilities, where they're really continuing to develop. And when those developments cease, and people just you know, relax into couch potato status—Why then I suppose we'll see declines. Or, when they burn out. You know, I think there's a sense in which you burn out in domains of expertise too. If you look around at people who become top-notch in anything, they stay there awhile and then start to—they go into another field for a bit, come off of that field. That's probably true of how most areas of expertise develop

(7) Click here to watch Dr. Horn talk about how his work in intelligence has impacted his work in other areas:

And I think my work on other areas is—Well, my work on general personality, my wish to understand the total person, if you will—And in that I see cognitive abilities as just an aspect of personality. So, my work on cognitive capabilities very much relates to my understanding of values and beliefs—very much relates to my understanding of abilities and motivations and drives. And they're all—To my mind, they're all interrelated. So my work on abilities informs that work, and my work on that kind of domain informs my work on abilities. So for example, when I'm studying children who have been abused or neglected I'm very much interested in how their abilities are being affected and how their abilities are affecting their development. At the same time I'm trying to comprehend how their motivations are being affected and how their sense of self and their—how their comprehension of their society and their universe and how—I'm very much trying to understand the whole person, and abilities is part of it. So, yeah. It informs my study of other things, and my study of other things informs my study of cognitive abilities.

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