Recognition is easier than recall. Multiple-choice tests are generally easier than fill-in-the-blanks tests or essays because it is easier to recognize the correct answer out of a group of possibilities than it is to have to dredge up the answer out of one’s own head.
Still, in order to be able to recognize the correct multiple-choice answer it has to be “somewhere” in one’s brain; otherwise there’s nothing to recognize. Someone with zero knowledge of a topic does no better than random chance on a multiple-choice test because all of the answer choices are equally meaningless to him. And someone with mastery of a topic can fill-in-the-blanks or can write an essay.
Think of your brain like a file cabinet, with tons of information stored in it. When you recognize a piece of information, it’s like the tab on a file folder in your head; the whole file folder now gets pulled up. By writing down anything you know about a problem, getting started in any possible way, you are hopefully going to write something that you then recognize, and your brain is going to pull the tab and bring up the rest of the folder.
Your brain contains over four terabytes of information (which is way too big a number to imagine), yet your working memory, the part of your brain that consciously works on a problem, can only hold about seven bits at any time. It’s as if your brain is a library, full of knowledge, yet you’re restricted to using a table only as big as a postage stamp.
Think about how impossible it is to multiply big numbers in your head, but how easy it is on paper. Your brain knows how to multiply, but it can’t keep track of all those digits.
This is why writing was invented in the first place. People found themselves with way more knowledge than they could hold and work with in their heads, and so they invented a way to put information “out there;” they scratched it in the dirt or into clay tablets or they inked it onto papyrus or paper.
Once people invented writing they could work with …