Our understanding of the role of long-term memory in human cognition has altered dramatically over the past few decades. It is no longer conceived as a passive repository of discrete, isolated fragments of information that permit us to repeat what we have learned. Nor is it seen only as a component of human cognitive architecture that has merely peripheral influence on complex cognitive processes such as thinking and problem solving. Rather, long-term memory is now viewed as the central, dominant structure of human cognition. Everything we see, hear, and think about is critically dependent on and influenced by our long-term memory.
After citing De Groot’s discovery and its subsequent expansion by Simon and Chase, and then several others, they sum up:
We are skillful18 in an area because our long-term memory contains huge amounts of information concerning the area. . . . Without our huge store of information in long-term memory, we would be largely incapable of everything from simple acts such as crossing a street . . . [to] solving mathematical problems. Thus, our long-term memory
incorporates a massive knowledge base that is central to all of our cognitively based activities. . . . The aim of all instruction is to alter long-term memory. If nothing has changed in long-term memory, nothing has been learned.
All this was summarized in Anders Ericsson’s remark “There is no such thing as developing a general skill.” The point applies to all school-learned activities and subject matters. It applies in spades to language use and reading comprehension.
It’s a paradox that one of the most important educational insights in history, one with high currency in the world of cognitive psychology, should have arrived just at the time when the fad for twenty-first-century non–domain specific, nonexistent skills should have reached a climax in the education world.
From 1946 to 1970, psychologists conducted experiments in language whose results showed why shared background knowledge is key to
language use. Given the memory limitations of the human brain, first analyzed decisively in 1956 by George A. Miller (another giant of psychology), it is impossible for us to say everything we need to say to make ourselves understood in conversation or on the page. If one does not manage to imply meaning, and do so quickly, the reader will lose the thread.
The limit of working memory permits just a few chunks to be held in mind at a time, before some of the chunks start dropping out in as little as a few seconds. That’s the limit of what needs to be made meaningful and placed in our long-term memory store before we forget what we are hearing or reading. The constraints of working memory turn a normally good reader into a poor reader when the topic is unfamiliar.
For, as George A. Miller pointed out, the only way to overcome the severe limitations of working memory is to “chunk.” That’s what grandmasters did with past chess games. That’s why the telephone
companies group numbers into three chunks resembling words (226-487- 2234) instead of nine digits that would be impossible to remember
(2264872234). Then when the chunks are forwarded to our long-term memory, we can lodge them and retrieve them more or less permanently.
This interchange between short-term memory and long-term memory is the basic structure of our mental life.
In language, more is always silently implied than what is explicitly said.
But such implications can work only if both speaker and listener are on the same wavelength, which is an apt metaphor for “sharing the same
knowledge and assumptions.” To be on the same wavelength on the radio means that the station that is broadcasting the signal and the radio that is receiving it are both tuned to the same frequency for the same carrier signal.
Short-term memory is a stern disciplinarian. Its rules cannot be broken. It turns chess masters into novices when the domain is unfamiliar. George Miller discovered in his pathbreaking paper that the way to make short-term memory work effectively is to chunk, so that twenty-one pieces become six or fewer. The chess masters’ well-stocked long-term memories enabled them to reproduce twenty-one pieces correctly so long as the chess
positions in question were taken from actual games. A well-stocked, well- selected, well-practiced long-term memory is the secret of expertise.
Important educational implications clearly follow from this research.
Note first that it refutes the familiar claim of American educators that you don’t need to learn a lot of “mere facts,” because you can always look them up on Google. Not so. Cognitive scientists have firmly established that you can’t understand what Google is saying unless you already know a lot of the facts Google is assuming you know on the subject in question.
In another insightful article entitled “How Children Learn Words,”
George A. Miller and Patricia M. Gildea found that, in the absence of prior relevant knowledge, reference works like dictionaries and encyclopedias are often useless. For, in the absence of relevant, preexisting knowledge, the inferences that a person makes when consulting a reference work can be inadequate and distorting. He asked a group of children to look up some words and then use them in a sentence. Here are some examples:
CORRELATE: “Me and my parents correlate, because without them I wouldn’t be here.”
METICULOUS: “I was meticulous about falling off the cliff.”
REDRESS: “The redress for getting well when you’re sick is staying in bed.”
RELEGATE: “I relegated my pen pal’s letter to her house.”
TENET: “That news is very tenet.”
S
o much for looking things up on Google if you are a fact-free novice. To explain the last example, Miller and Gildea exhibited the dictionarydefinition of tenet: “A principle, belief, or doctrine generally held to be true; especially: one held in common by members of an organization, movement, or profession.” The child had grabbed hold of the word “true,”
applied the adjective, and came up with “That news is very true,” which makes sense, whereas “That news is very tenet” is hilariously mysterious.
In light of now well-established scientific consensus, the principle of domain-specific knowledge as central to skills like critical thinking should be accepted by all rational people as truth. It demolishes the claim that our schools are teaching all-purpose skills like critical thinking through ad hoc child-chosen or teacher-chosen content. The general-skills myth has
endured partly because it has enabled high officials to avoid the criticism
and controversy that attends the actual specification of content. The persistence of the myth of critical thinking enables them to sidestep responsibility with a good conscience.
We need to let them know the emphatic scientific consensus. It is essential that the public demand specific grade-by-grade content in our elementary schools, so that one grade can build on another in a systematic way, a kind of schooling that is best for all students and especially
beneficial to our least-advantaged students.
Chapter 6
The Lessons of Educational Failure and Success around the World
W
e have now seen how child-centered romanticism has caused American schoolchildren to slide downhill in their verbal scores. The same pattern has confounded other nations that have adopted child-centered romanticism.The “nature knows best” theory didn’t start in the United States. Western Europe is the home of educational romanticism, with America its secondary residence. When American prestige rose after World War II, people in
Europe began to think, “Maybe we should imitate the Americans.”
In the late twentieth century, Germany, Sweden, and France experienced the same educational failures as in the United States, and from those same mistakes—though in two of those nations educational leaders were smart enough to rectify their errors and help their nations rise again nearer to the top. In Asia, China and Japan did not even momentarily experience such failures. They scorned the nineteenth-century romantic ideas about
individualizing content in the classroom. As a result, schools in the Far East have continued to improve and now score at or near the top in international comparisons.