In his excellent book A Question of Intelligence: The IQ Debate in America, former Fortune magazine editor Daniel Seligman describes what it’s like to take the WAIS-R IQ test.  One page 6-7, he describes taking the Block Design subtest, a measure of visual analytical reasoning:

Block Design requires you to work with plastic blocks.  Each has two red sides, two white sides, and two sides divided diagonally between red and white.  The examiner first shows you the design pattern, then scrambles the blocks on the table and asks you to assemble them so as to recreate the pattern.  Some of the patterns require you to manipulate nine blocks, some only four.  Anybody, even I, can do the design if given enough time; unfortunately, the time you take is factored into your score.  On the first eight efforts, I did finally manage to replicate the designs, but my times were generally terrible.  On the ninth effort, I gave up in frustration, even though I clearly had eight of the nine blocks in place.

From this description, it seems that Seligman passed all but the ninth item, but got zero bonus points for quick performance, suggesting a raw score of 32/51.  According to the WAIS-R manual, this equated to a scaled score of 10 in the peak age group (20-34) and a scaled score of 13 in Seligman’s age group (55-64).

But because WAIS-R norms were a decade old when Seligman was tested, and the Flynn effect increased WAIS Block Design scaled scores by 0.41 points a decade from 1978 to 1995 (Flynn, 2012), his scaled scores must be reduced to 9.59 and 12.59 respectively.  An age adjusted scaled score of 12.59 is equivalent to an above average IQ of 113 (U.S. norms; 111 U.S. white norms) on that subtest.

The great Jewish New Yorker David Wechsler (founder of the WAIS) thought Block Design (invented by Kohs but adapted to the Wechsler scales) was an excellent measure of general intelligence and it remains the most culture fair IQ subtest I have ever seen.  Sadly, Wechsler found that as he got older, he could no longer perform well on his own Block Design test, causing him to obsessively pester friends with questions about what it truly means to be an intelligent adult.  Had I been one of his friends, I would have said “It means the cognitive ability to adapt: to take whatever situation you’re in, and turn it around to your advantage.”  On the Block Design subtest, one must literally turn the blocks around to adapt them to the desired design.

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