re:
Larry Summers' claim that "in a world where the entire Library of Congress will soon be accessible on a mobile device..., factual mastery will become less and less important":
Larry Summers is wrong.
Factual mastery has not and will not become less important, for the simple reason that
it is not possible to think about something stored on Google.
While you are thinking about something, that something has to be lodged inside working memory, not Google.
Biology does not work the way Larry Summers thinks it works.
Working memory
If I ask you to multiply 36 by 3 inside your head, working memory is what you use to do it.
Working memory (WM) does three things:
- Holds the problem -- "multiply 36 by 3" -- in consciousness
- Retrieves the relevant knowledge from long-term memory (the times tables, in this case)
- Performs the calculation
Boiling it down, working memory is:
- a form of storage
- a search engine
- a "computer" or thinker
"Critical thinking" is accomplished by working memory.
3 to 5
The fact that we can think only about things stored inside working memory leads directly to the need for "factual mastery."
Factual mastery—knowledge stored inside long-term memory—is essential because although long-term memory is vast, working memory is tiny:
...cognitive tasks can be completed only with sufficient ability to hold information as it is processed. The ability to repeat information [you have just heard or read] depends on task [difficulty]... but can be distinguished from a more constant, underlying mechanism: a central memory store limited to 3 to 5 meaningful items in young adults.
The Magical Mystery Four: How Is Working Memory Capacity Limited, and Why? by Nelson Cowan
Working memory can hold three to five items at once. That's it. That's the limit.
Three to five.
I hit this limit all the time trying to write about new topics. The
basal ganglia, for instance. For well over a year, I have been endlessly working and re-working a project on the
basal ganglia, a subject I knew essentially nothing about going in. Where the basal ganglia were concerned, my long-term memory was a blank slate.
The upshot: I was not able to write about the basal ganglia until I actually
learned about the basal ganglia:
learned as in committed the material to memory. It didn't matter how many times I looked up
basal ganglia on the internet. I looked up the
basal ganglia on the internet a lot, as a matter of fact; then I forgot whatever it was I had looked up while I was looking up something
else to do with the
basal ganglia, after which I'd have to go back and re-look up the first thing all over again.
Try it if you don't believe me.
Here are some terms related to the
basal ganglia:
Dorsal striatum
Ventral striatum
Putamen
Nucleus accumbens
Ventral tegmental area
Orbital frontal cortex
Dopamine
Two pathways
OCD
Addiction
Habit
Impulsive
Compulsive
Intuition
Probabilistic learning
Associative learning
Statistical learning
Serotonin
Orbitofrontal cortex
Cortico-striatal circuit
Now supposing I handed you a laptop and asked you to look up each term on Wikipedia, then write a coherent, reasoned 5-paragraph essay on the basal ganglia: what it is and what it does. Just a quick summary organized into 5 coherent paragraphs.
You couldn't do it.
You couldn't do it because every time you wrote about the ventral striatum, the dorsal striatum, and the orbitofrontal cortex, you would forget the VTA and the putamen—and you would forget the VTA and the putamen because your working memory will hold only 3 to 5 things at once. Something has to go.
That's what happened to me
when I took the SAT with a calculator I didn't know how to use. Each time I swapped the steps for using the calculator
into working memory, my brain swapped the information for the problem I was doing back
out of working memory. Then, when I tried to cram the information for the problem back into working memory, the calculator steps got squeezed out
again.
I could remember the problem, or I could remember the calculator, but I couldn't remember both at the same time. Too much information, literally.
My calculator fiasco illustrates the reason you need to practice until you learn content and skills to the point of '
automaticity.' (
Automaticity is another
basal ganglia term, by the way. The
basal ganglia are the part of the brain that underpins automaticity.) Once you've learned something so well you don't have to think about it, you free up space in working memory to hold other things.
Thus if you know the times tables "by heart," you don't need to pull "3x6=18" into working memory. Working memory can locate "3x6=18" inside long-term memory and use it without displacing "36x3."
Knowledge stored inside the brain is different from knowledge stored outside the brain
Experts always possess factual mastery of their fields.
Always.
The reason experts always possess factual mastery of their fields is that knowledge stored in long-term memory is different from knowledge stored on Google.
Knowledge stored in long-term memory is (or becomes) biologically connected, or "
chunked." Thus to an expert on the basal ganglia, ten facts about the basal ganglia are just one or two
big facts about the basal ganglia.
Chunking is the magic,
because working memory doesn't care about chunk size. Working memory can hold 3 to 5 small and simple items
or 3 to 5 large and complex items. Either will do. Chunking gets around the limits on working memory.
Dan Willingham's demonstration of working memory
For a demonstration of the chunking principle, read the list below, then look away and try to remember what you've read:
CN
NFB
ICB
SCI
ANC
AA
How many letters did you recall?
To find out how many letters you would have recalled via prior chunking inside long-term memory, see Daniel Willingham's explanation in
"How Knowledge Helps" (American Educator | Spring 2006).
(The answer is all of them.)
You can't Google knowledge chunks
Knowledge chunks can be created only
inside the brain, via
learning.
You can't Google someone else's complex knowledge chunks and swap them into your own working memory. It doesn't work that way. Your own brain has to do the work of chunking, and your brain does that work through the process of learning, bit by bit and step by step.
Which means that the process of storing content in long-term memory is not a simple matter of "memorizing facts" so you can "
regurgitate" them later.
Over time, memorization creates the complex knowledge chunks that allow knowledgeable people to engage in complex thought.
Experts think better than novices because experts have factual mastery
To a gratifying degree, I can now think about nearly all 19 items on the basal ganglia list at the same time. I'm still struggling with "putamen" and "ventral tegmental area," but the other 17 are stored in memory: my memory, not Google's. So, for me, those 17 items are no longer 17 separate items, but closer to 2 or 3. When I think about 1 item on the list, I'm thinking about the others.
I reached this point by committing these terms and concepts to memory. As the terms entered my long-term memory, they became
biologically connected and chunked. Now that I can think about them at the same time, which means I can write about them, too.
What makes experts expert, to a large degree, is factual mastery of their fields. Factual mastery allows experts to think deeply and well because the content they are thinking about has been
biologically connected and chunked inside their brains, and there is no obvious limit to the amount of chunked content working memory can manage so long as knowledge has been chunked into no more than 3 to 5 separate entities.
Factual mastery is required for complex thought.
Which brings me back to Larry Summers.
If our schools are going to ask students to 'think' about material they haven't learned, students are going to be thinking about 3 to 5 small, not-well-elaborated items at a time. Period. Their thinking will be superficial, and the conclusions they reach will be superficial, too.
Which is exactly what we see in Larry Summers' op-ed about education, a field in which he is neither expert nor learned.
AND SEE:
Superior Memory of Experts and Long-Term Working Memory (LTWM)
Extremely fast learning & extended working memory
The Number and Quality of Representations in Working Memory by Weiwei Zhang and Steven J. Luck
How Knowledge Helps by Daniel T. Willingham American Educator Spring 2006
#whystudentsneedtomemorize
