The Knowledge Architects: Building Wisdom in the Information Age

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Episode Summary

Show a chess master a position from a real game for about three seconds, then take it away. They will rebuild almost all of it from memory. An ordinary club player will manage about half. Now scramble the same pieces into a random arrangement and show it again, and most of that advantage disappears. It is the most replicated finding in the psychology of expertise, and the conclusion drawn from it is substantially correct: expertise is not a bigger memory but a better organized one. Almost every specific claim usually attached to it, however, is wrong in some interesting way.

In this episode we look at how years of experience reorganize perception itself. We follow Adriaan de Groot from the 1938 AVRO tournament to the recall study of 1944 that had four participants, one of whom was de Groot. We watch William Chase and Herbert Simon turn a vague idea into something you can count, and then watch Simon go back 23 years later to correct his own most cited claim. Along the way we find out where the famous figure of 50,000 chunks actually came from, what an expert's eyes are doing that yours are not, and why the same perceptual machinery that makes a master brilliant can briefly make them perform like a player 600 rating points weaker.


Key Topics Covered

  • De Groot's two experiments: thinking aloud at AVRO 1938, and the separate recall study of 1944
  • Grandmasters do not search deeper (6.8 versus 6.6 half moves) and they decide faster
  • Where the famous 93 / 72 / 51 recall figures come from, and the four people behind them
  • Why de Groot never tested a novice, and how his own word "Expert" began 60 years of miscitation
  • Chase and Simon make a chunk measurable: the copy task and the rule of two seconds
  • The prediction that failed: their master had more chunks, not only bigger ones, and they said so in print
  • The scrambled board control, and the three subject study the textbook claim rests on
  • Gobet and Simon 1996: thirteen experiments, twelve of them contradicting the received version
  • Why a small residual advantage on random boards is decisive rather than embarrassing
  • Vicente and Wang name the falsifying experiment, Gobet and Waters run it, the effect survives
  • Where 50,000 chunks came from: an extrapolation from a program that knew about a thousand patterns
  • Templates, and how the size of a human hand distorted a foundational constant of cognitive science
  • The same pattern in programming, electronics, music, Go, bridge, sport and radiology
  • Where it fails, and why the failures cluster in the smallest samples
  • Expert visual span: about 23 squares on a real position, about 9 on a scrambled one
  • Perceptual automaticity: experts cannot choose to stop seeing what they see
  • Klein's fireground commanders and decisions made by recognition rather than comparison
  • Kahneman and Klein's two conditions for trusting an intuition
  • Fractionated expertise, and why confidence is not the signal
  • The Einstellung effect: how a familiar good solution blocks a better one
  • Drew's radiologists and the gorilla they looked straight at

Researchers Mentioned

  • Adriaan de Groot (1914 to 2006, Netherlands) : Chess master and psychologist, ran the studies that founded the field
  • William G. Chase (Carnegie Mellon) : Wrote "Perception in chess" with Simon, and made the chunk operationally measurable
  • Herbert A. Simon (1916 to 2001, Carnegie Mellon) : Nobel laureate and Turing Award winner, author of the chunking theory and, later, of its correction
  • Fernand Gobet : Chess international master and psychologist, template theory, CHREST, and the random position correction
  • Max Euwe : Former world chess champion, the grandmaster in de Groot's recall study
  • Neil Charness : Eye movement studies of chess expertise, and skill in bridge
  • Eyal Reingold : Visual span and perceptual automaticity in chess players
  • Merim Bilalić : The Einstellung effect, and the citation history of de Groot
  • Judith Reitman : Skilled perception in Go, the domain where the chunking method broke
  • Ben Shneiderman : Chunking in programmers
  • Dennis Egan and Barry Schwartz : Symbolic drawings, where scrambling let the novices win
  • Harold Kundel and Calvin Nodine : Radiologists interpreting chest films without visual search
  • Trafton Drew : The invisible gorilla in the CT scan
  • Gary Klein : Fireground commanders and recognition as decision making
  • Daniel Kahneman (1934 to 2024) : With Klein, the conditions for intuitive expertise
  • Philip Kellman and Patrick Garrigan : Perceptual learning as the underlying mechanism
  • Kim Vicente and Jiajie Wang : The critique that named the decisive experiment
  • Giovanni Sala : Pooled the evidence on expert recall of random material across many domains

Key Studies and Sources

  • de Groot, A.D. (1946). Het denken van den schaker. Amsterdam: North-Holland. [English: Thought and Choice in Chess, The Hague: Mouton, 1965]
  • Chase, W.G. and Simon, H.A. (1973). "Perception in chess." Cognitive Psychology, 4(1), 55-81.
  • Simon, H.A. and Chase, W.G. (1973). "Skill in chess." American Scientist, 61(4), 394-403.
  • Simon, H.A. (1974). "How big is a chunk?" Science, 183(4124), 482-488.
  • Simon, H.A. and Gilmartin, K.J. (1973). "A simulation of memory for chess positions." Cognitive Psychology, 5(1), 29-46.
  • Gobet, F. and Simon, H.A. (1996). "Recall of rapidly presented random chess positions is a function of skill." Psychonomic Bulletin and Review, 3(2), 159-163.
  • Gobet, F. and Simon, H.A. (1996). "Templates in chess memory: A mechanism for recalling several boards." Cognitive Psychology, 31(1), 1-40.
  • Gobet, F. and Simon, H.A. (1998). "Expert chess memory: Revisiting the chunking hypothesis." Memory, 6(3), 225-255.
  • Vicente, K.J. and Wang, J.H. (1998). "An ecological theory of expertise effects in memory recall." Psychological Review, 105(1), 33-57.
  • Gobet, F. and Waters, A.J. (2003). "The role of constraints in expert memory." Journal of Experimental Psychology: Learning, Memory, and Cognition, 29(6), 1082-1094.
  • Sala, G. and Gobet, F. (2017). "Experts' memory superiority for domain-specific random material generalizes across fields of expertise: A meta-analysis." Memory and Cognition, 45(2), 183-193.
  • Bilalić, M., McLeod, P. and Gobet, F. (2008). "Inflexibility of experts: Reality or myth? Quantifying the Einstellung effect in chess masters." Cognitive Psychology, 56(2), 73-102.
  • Bilalić, M., McLeod, P. and Gobet, F. (2008). "Why good thoughts block better ones: The mechanism of the pernicious Einstellung (set) effect." Cognition, 108(3), 652-661.
  • Reingold, E.M., Charness, N., Pomplun, M. and Stampe, D.M. (2001). "Visual span in expert chess players: Evidence from eye movements." Psychological Science, 12(1), 48-55.
  • Charness, N., Reingold, E.M., Pomplun, M. and Stampe, D.M. (2001). "The perceptual aspect of skilled performance in chess: Evidence from eye movements." Memory and Cognition, 29(8), 1146-1152.
  • Reingold, E.M., Charness, N., Schultetus, R.S. and Stampe, D.M. (2001). "Perceptual automaticity in expert chess players: Parallel encoding of chess relations." Psychonomic Bulletin and Review, 8(3), 504-510.
  • Shneiderman, B. (1976). "Exploratory experiments in programmer behavior." International Journal of Computer and Information Sciences, 5(2), 123-143.
  • Egan, D.E. and Schwartz, B.J. (1979). "Chunking in recall of symbolic drawings." Memory and Cognition, 7(2), 149-158.
  • Reitman, J.S. (1976). "Skilled perception in Go: Deducing memory structures from inter-response times." Cognitive Psychology, 8(3), 336-356.
  • Kundel, H.L. and Nodine, C.F. (1975). "Interpreting chest radiographs without visual search." Radiology, 116(3), 527-532.
  • Coughlin, L.D. and Patel, V.L. (1987). "Processing of critical information by physicians and medical students." Journal of Medical Education, 62(10), 818-828.
  • Drew, T., Võ, M.L.H. and Wolfe, J.M. (2013). "The invisible gorilla strikes again: Sustained inattentional blindness in expert observers." Psychological Science, 24(9), 1848-1853.
  • Kahneman, D. and Klein, G. (2009). "Conditions for intuitive expertise: A failure to disagree." American Psychologist, 64(6), 515-526.
  • Kellman, P.J. and Garrigan, P. (2009). "Perceptual learning and human expertise." Physics of Life Reviews, 6(2), 53-84.

Key Numbers to Remember

  • 3.5 seconds : the average exposure in de Groot's 1944 recall study
  • 93 / 72 / 51 percent : recall by grandmaster, expert and club player in that study
  • 4 participants : the entire sample, one per skill level, including de Groot himself
  • 6.8 versus 6.6 half moves : maximum search depth for grandmasters versus experts, and the grandmasters were faster
  • 2 seconds : the pause length Chase and Simon used to mark the boundary between chunks
  • 2.5 pieces : the average size of their master's chunks, against 1.9 for the beginner
  • 7.7 versus 5.3 chunks : the finding that contradicted their own prediction
  • 12 of 13 experiments : skill predicted recall of random positions, p = .0017 (Gobet and Simon 1996)
  • 1 piece versus 5 pieces : the recall gain per 400 Elo points on random boards versus real ones
  • 49 of 55 experiments across domains favoured the experts (Sala and Gobet 2017)
  • 50,000 chunks : an extrapolation, not a measurement, from a program holding about 1,000 patterns
  • 25,000 to 100,000 : Simon's own published range, of which 50,000 is the geometric mean
  • 300,000 nodes : what the CHREST simulation needed to reach master level, and it still fell short
  • 23 squares versus 9 : the expert's useful visual window on a real position versus a scrambled one
  • 253 versus 244 ms : fixation duration for experts versus intermediates, a difference of nothing
  • 386 ms versus 0 ms : how much a helpful visual cue saves a novice, and how much it saves an expert
  • 105 ms : how much slower an expert becomes when told to ignore a piece that gives check
  • 18 percent and 0 percent : Masters and Candidate Masters finding the better solution when a familiar one is present
  • 100 percent : the same players finding it once the familiar solution is disabled
  • 83 percent of radiologists missed a gorilla in a CT scan at 48 times the size of a lung nodule
  • 70 percent true positives on chest films seen for 0.2 seconds, before the eyes can move
  • 10.2 versus 2.3 lines : the expert advantage in recalling working code versus scrambled code

Memorable Quotes

"It is thus beyond doubt that the depth of calculation cannot be the prime distinguishing characteristic between the grandmaster and the expert player."
Adriaan de Groot, Thought and Choice in Chess

"M does not calculate more than E... M sees more than E, especially the more important things."
Adriaan de Groot

"What was once accomplished by slow, conscious deductive reasoning is now arrived at by fast, unconscious perceptual processing. It is no mistake of language for the chess master to say that he 'sees' the right move."
Chase and Simon (1973)

"Contrary to our expectation, the number of chunks is related to chess skill."
Chase and Simon (1973), reporting the failure of their own prediction

"At the moment, we have no good explanation for the discrepancy, but have simply placed it as an item high on the research agenda."
Simon and Chase (1973)

"In all cases, except in Chase and Simon's (1973b) study, recall performance increases monotonically as a function of skill."
Gobet and Simon (1996)

"Though the patterns are produced by chance, they will be recognized if already stored in memory, as in noticing 13 spades in a hand dealt at bridge."
Gobet and Simon (1996), footnote 4

"The novice chess player may be blind to the impending checkmate that jumps out at the expert."
Kellman and Garrigan (2009)

"Intuition is nothing more and nothing less than recognition."
Herbert Simon, quoted approvingly by Kahneman and Klein (2009)

"There is no subjective marker that distinguishes correct intuitions from intuitions that are produced by highly imperfect heuristics."
Kahneman and Klein (2009)

"You'll have to find a harder problem than this. No Master would miss the shorter solution in this position."
an expert predicting the Einstellung results. The actual figure for Masters was 18 percent.

The Big Idea

Expertise is not a faster mind or a bigger memory. It is a perceptual vocabulary: tens of thousands of meaningful patterns, learned slowly, that let an expert see structure where a novice sees parts. That vocabulary has three stubborn properties. It is earned, one pattern at a time, which is why there is no shortcut. It is domain bound, which is why a grandmaster's memory for the same pieces arranged meaninglessly is an ordinary memory. And it is automatic, which is the cost: once a familiar pattern fires, you cannot choose to stop seeing it, and you will feel as though you are still searching when your eyes have already stopped. The episode is also a case study in how science corrects itself. Nearly every wrong detail in the popular version of this story was fixed by the same researchers who introduced it, in print, under their own names, and the corrected version turned out to be stronger than the tidy one.


Next Episode Preview

Episode 32: Deliberate Practice : If expertise is a vocabulary of tens of thousands of patterns, where does it come from? The models put the cost of fixing a single new chunk in long term memory at something like eight seconds, which tells you nobody arrives here quickly. We look at what those years have to contain, why simply doing something for ten thousand hours does not work, and what Anders Ericsson spent his career trying to correct about the way his own research got told.


What is The Knowledge Architects: Building Wisdom in the Information Age?

AI-generated audio: both hosts and their conversations are created by AI, not by real people.

The Knowledge Architects is a free, science-based podcast exploring how we learn, remember, and organize knowledge. Each episode translates peer-reviewed research from cognitive science, neuroscience, and psychology into practical insights, helping you understand how your mind works and how to work with it more effectively. Our team chooses every topic and edits each episode. The research is drafted with AI and read by us before publishing. Brought to you by ElysFlow.