Deming's preferred approach to teaching was the Socratic method. As a helper at his seminars, I saw how effective this approach was many times. I recall one such instance in 1988. Deming was discussing the importance of knowing what numbers mean before performing any statistical analysis. "It's harder than we might think," he said. Then he asked, "How many people are in this room? There isn't any answer to that question."

After the main session, I facilitated a discussion group trying to determine just what Deming meant. The group was from the same company and had attended together, so they could take back different perspectives on Deming's philosophy. We gathered around a poolside patio table, enjoying the warm Southern California sun.

"It doesn't make any sense to me," declared Bill, their senior manager. "Of course, there is an answer to that question. And it's easy to determine, too. You just count the people in the room."

Heads nodded in agreement. The group seemed about to reach a consensus that Deming simply had misspoken. I was pretty sure he hadn't, but I wanted them to conclude that on their own. Suddenly, I knew how I would do it.

"How many people are here?" I queried them.

They looked at me like deer caught in headlights.

"What do you mean?" asked Gaylene.

I decided to excuse myself, lest I succumb to the temptation to lecture. "I have to help another group right now," I lied. "I'll be back in half an hour to hear your answer. It's a simple question, so that should be plenty of time."

Thirty minutes later I returned. The group was embroiled in intense discussion and didn't notice me.

"So, what's the answer?" I interrupted them. "How many people are here?"

"We don't know the answer yet," Bill retorted angrily. "And you lied to us. It's not a simple question at all. We need a lot more information."

"Such as?"

"Such as, when you say 'here,' do you mean this table, the pool area, the patio or what?" prompted Nancy.

"And when you say 'people,' do you mean guests only, or do you include staff, delivery people and cabbies looking for their fares?" asked John.

"And do you mean here now?" asked Beverly. "What about people who left to go to the restroom or get a towel? Do they count?"

"What do you think?" I barked, doing my best imitation of Deming's teaching method. The group pondered for a moment.

"I guess that depends on what we will use the number for," ventured Jacob. "If we want to know how many guests use the pool facilities, we wouldn't count staff or delivery people."

"Right, and if we want to determine how many outside tables the restaurant needed, we wouldn't count people in the pool," agreed Bill.

"And to really answer the question for a particular purpose, we'd have to repeat the count at different times," observed Beverly. "This place is crowded now, but it was empty this morning."

The group sat silently for a moment, each person mulling over the discovery they'd just made.

Bill's eyes widened noticeably as a thought occurred to him. "Do you remember that flap we had last year with our No. 1 customer about those ceramic substrates? The customer said our parts had voids, but our quality control people said they didn't. We jumped all over our inspectors after those parts were returned. Remember?" All heads nodded in unison.

"I remember handing the bag of rejects to my inspectors and demanding an explanation," continued Bill. "One of them looked at several substrates and said she didn't see any voids. Another used an eye loop and said he thought he saw some small voids. A third put a sample under a stereo microscope and said the problem wasn't voids but pits."

Bill looked around the table, his thoughts still focused on that conversation. "I told the inspectors the problem was simple," he recalled. "All they had to do was count the voids."

"Yeah," said Rachael, "like counting how many people were in the conference room today."

"OK, people," said Bill, turning to a fresh page in his notebook. "Let's see if we can operationally define a void tonight."