A Handbook of Intelligence

This review appeared in Intelligence in 2012. 

The Cambridge Handbook of Intelligence. Edited by Robert J. Sternberg and Scott Barry Kaufman. Cambridge University Press, New York, NY. ISBN 978-0-521-73911-5. XIX, 885 pages.

A Sternberg handbook on intelligence is a welcome part of any psychologist’s library, and a new volume arouses pleasurable anticipation. Weighing in at 1.7 Kilos and almost a thousand pages, it is a small library in itself, guaranteeing that there will be much to enjoy and reflect upon.  Of the 84 authors only 12 are not from the USA and Canada. Four of that dozen are from Britain, 2 from Singapore, 1 from New Zealand, 1 from Australia (incorrectly classified as USA) 3 from Austria/Germany, and 1 from Russia, though she is also half-time in the USA. From the above it can be deduced that the cleverest people in the world come from Britain and its former colonies, a clear vindication of its lingering sense of exceptionalism.  The result is a pleasing preponderance of Anglo-Saxon empiricism, tempered by a moiety of Teutonic perfectionism. However, the majority of individual examples, legislative frameworks and historical references are US centric, 312 million citizens being given precedence over the other 7 billion. It is natural to search for truth where the light is brightest, and the grants most generous, but the results and the frames of mind may lack representativeness.

Residence in a nation state need not blind the authors to the global panoply of human accomplishment, so perhaps the deeper analysis is to turn to the back of the book and ask: “Who do these authors admire”? I list in ascending order the total number of pages on which the most popular authors are mentioned, for brevity setting 20 pages as the minimal entrance qualification: K.W.Fisher 21, R.E.Nisbett 21, C.J. De Young 21, P.Salovey 22 , O.Wilhelm 22, A.Binet 23, J.R.Flynn 23, R.D.Roberts 23, A.S.Kaufman 24, A.R.A.Conway 25, D.K.Detterman 25, K.A.Ericsson 25, J.R.Gray 25, S.B.Kaufman 26, D.Wechsler 26, J.D.Mayer 28, R.W.Engle 29, R.B.Cattell 34, P.L.Ackerman 35, S.J.Ceci 35, J.L.Horn 35, J.B.Carroll 38, C.Spearman 41, K.E.Stanovich 44, E.L.Grigorenko 46, A.R.Jensen 48, H.Gardner 58, I.J.Deary 71, R.J.Sternberg 156.

Is the list representative of the most accomplished and impactful thinkers? Readers will have their own preferences, and can compare the list with the usual citation indexes, but my own reaction is that (all artefacts aside) there are several names likely to gain general approval, some absences, and several surprises.  Daniel Kahneman, our one psychologist/economist Nobel Laureate does not make the cut, meriting 11 page mentions. There is a paper in this for someone.

Finally, one has to ask the indelicate question: “How intelligent are the authors”? None of them should flinch from this evaluation, but should metaphorically sit down next to thousands of test takers and welcome it as a contribution to knowledge. It is evident that all of them have vast vocabularies, which suggest exceptionally high intellects. However, they appear weak in visuo-spatial skills. There are a few path analyses, some exemplars of test and experimental materials, a very few drawings, some developmental scales and tiers, and one sliced and labelled brain. The scarcity of illustration would shame any Upper Paleolithic cave. There is little to help a hard-pressed lecturer throw together some teaching slides. Perhaps there were cost constraints. The authors’ numerical skills are harder to evaluate. Some have included a few tables with numbers, the others, perhaps wisely, have not.  Numbers may turn out to be wrong. The end result (with honourable exceptions) is proof of the power and the limitations of words, and testimony to psychology’s lack of precision: all those hours of psychometric testing and data analysis resulting in a tentative “perhaps”. It is instructive that the latest findings in intelligence can be communicated with few models and numbers, in a way that genetics or physics would find difficult. Lastly, believers in multiple intelligences will understand that I was unable to judge the authors in terms of their musical, naturalistic, interpersonal, bodily-kinaesthetic, or indeed gastro-intestinal accomplishments.

Despite this necessarily unrepresentative sample of high achievers, there are many good chapters in this volume, with enough clarity, enthusiasm, novelty and reflection to engender intelligent thought in the reader. A mere sampling, in quasi-random order: Zentall’s explanations of cognitive dissonance and gambling in pigeons;  Gaborra and Russon’s evolutionary history of intelligence, which is like paging through an ancient family photograph album, waiting for one’s own likeness to emerge; Nettlebeck on the  basic processes of reaction and inspection times, confirming their moderate links with intelligence(0.3 to 0.5); Conway et al. making a case (0.5) for working memory tapping processes shared with fluid intelligence; Niu and Brass on the Confucian path to knowledge “some by natural ease, some by desire of its advantages, some by strenuous effort, but the achievement being made, it comes to the same thing”; Halpern et al. “on average, women and men live systematically different lives”; Flynn’s lucid prose partly illuminating the mystery of secular intelligence gains (some well-chosen numbers here) arguing that modernity has taught us to cope with abstraction (though the gains for the ultimate abstraction of mathematics are the smallest, and baby tests show the same overall secular gains, so it cannot all be due to the availability of heuristics); Suzuki et al. provide the better chapter on race and intelligence, though hereditarians may feel insufficiently represented; Barnett et al. discuss the effects of intelligence on national economies and give Rindermann’s betas for each finding; Deary et al. sit on top of the psychometric gold mine of population-wide longitudinal samples from whence the bullion of new results regularly flow, in this instance on intelligence’s astounding effects on health and lifespan; De Young on personality, saying of the relation between intelligence and openness to experience that(quoting Saucier)  “Intelligence perturbs the orbit of any construct that comes near to it”, and to give final word to a 6 year old child writing to his mentor in Feldman and Morelock’s chapter on prodigies and savants  “I am working on a unified theory. Are you? My unified theory is broken up into many parts, each part the size of special relativity. I really know my geometry… A rhombicosidodecahedron is the largest known polyhedron. It is huge!”  Humans have spectacular intelligence.

There is strength in depth, and much to enjoy, but also some lapses.  Some authors “correct” group ability differences for socio-economic-status without considering that these economic differences may be due in large part to prior intelligence. Cross-lagged designs in longitudinal studies may offer methodologically superior results. I would have liked a strong comparative study of the predictive utility of psychometrics-as-usual versus multiple-intelligences with respect to the full range of intelligence on a range of real world variables.  Some theoretical chapters placed stakes in the ground, but the foundations had yet to solidify. “Giftedness” seems heterogeneous and poorly defined. Some authors could have benefitted from reading Earl Hunt’s epilogue, particularly on stereotype threat and the non-existence of race, and then re-considering their arguments. 

So, do these intelligent and conscientious authors deserve to pass? Apart from some minor typographical errors, this examiner would recommend that, with some rebalancing of most-quoted authors and the revision of a few chapters, and a thorough factor-analytic pruning of the multiple intelligences section, the candidates should be encouraged to proceed to the next volume.

James Thompson