Fill the Pail, then Light the Fire.

"Education is not the filling of a pail, it's the lighting of a fire." So says nearly everyone who runs professional development and teacher training schools, as if anyone could ever think critically about something without any facts to think about.  You can't have a decent conversation about the Civil War unless you have a knowledge of who fought it and why, when and where the battles took place, the rhetoric and speeches from some of the major players and a sense of the history that led up to it. Harper's Ferry touched off the fuse, but WHY? Why was the country ready to light on fire? Was it about slavery or states rights or federalism? Who fought on which side? What's with the Stars and Bars? Which side still traded with England?

If you don't know some of the facts, your opinions and viewpoints are worthless.

It's the same in math. If you can't factor trinomials, then there are scads of things that you can't do much thinking about. If you spend three minutes to do a fraction addition that the rest of the class does in seconds, then your understanding of probability is delayed, if not severely impacted. If you reach for a calculator to add ½ and ⅔, it makes it difficult for you to focus on what you really wanted to accomplish.

Imagine a class of Korean and Japanese kids (like one I had some years ago).  All had limited English skills.  They were always looking up words in the dictionary instead of memorizing, always working out the meaning word by word, and always resisting when we said "Just use English ... We know it's hard but it will pay off."  One day, we finished our math work early and one asked me about a Reading homework (instantly, the rest chimed in).  They were having trouble understanding what was going on.

I read the story quickly, two or three pages, a minute or so. It told of a man who lived in the woods ... his wife disappears ... detectives can't find evidence but they're sure husband killed her ... husband had a tremendous pile of split firewood ... no body in the wood pile, in the house, buried ... they realized it was warm and he didn't need the wood to heat the house ... why so much split wood?  Then a detective says "Aha, to work up an appetite."

None of the students got it.  They were so wrapped up in the definitions of words, in the structure of the sentences, and meaning of sentences that they couldn't put it all together at once and understand the whole. They didn't have enough facts and basic understanding to do any critical thinking. The "can't see the forest for the trees" analogy.

As an experiment, I grabbed a couple of weaker American students, dyslexics and generally slow readers ... they all got it instantly ... "Ewwww." I grabbed some European kids who had more years in country ... they all got it instantly ... "That's gross." The Asian kids were still stymied, even while other kids tried to explain without giving it all away.

Lighting that fire should be your goal, but the facts and knowledge are the only things you have for fuel.

And the original wasn't Yeats, it was Plutarch:

For the mind does not require filling like a bottle, but rather, like wood, it only requires kindling to create in it an impulse to think independently and an ardent desire for the truth. Plutarch , page 259

Not that the Internet has a clue:
UPDATE:
You can vote it up on Joanne Jacobs for least favorite edu-homily.