A few years ago, I was helping students prepare for the essay part of their exam covering research designs. Students had been at the whiteboards brainstorming the content that they needed to include in an answer comparing correlational with experimental designs. As we went around the room, students were saying things like, “A correlational design doesn’t manipulate an independent variable but an experiment does,” and “A correlational design doesn’t control for extraneous variables, but an experiment does.” In discussing how to form an effective answer, I explained that a good answer would include an explanation of what the correlational design actually did, rather than or in addition to what it didn’t do.  The students struggled to understand my point. “Let’s say,” I explained, “that you asked me what area I specialized in within psychology and I told you that I didn’t specialize in psychophysics. How helpful was my answer?” They were starting to get it.

My doctoral committee chair, who was also my major professor, was a staunch supporter of striking the word “not” from his professional writing. I had long since developed the habit of eliminating the word from my own writing but had yet to embrace the concept in my teaching. On that day, I finally did. I explained to my students that one should always say what is rather than what is not. To put my teaching where my writing habit was, I offered my students one bonus point for each time I said the word “not” during the remainder of the class period. Despite my attempts to avoid it, I used the word “not” eight times. “I was not going to make that mistake again.” My students laughed, pointed at me, “You said, ‘not’!” They would then repeat what I had said and I would have to restate my point. “I was going to avoid making that mistake again.” “I was not happy with” became “I was annoyed with.” “Who didn’t turn in their work?” became “Who failed to turn in their work?” (Ouch!). My mistakes were a boon, however, because students were able to experience me rephrasing “not-statements” into statements. By the end of class, they got it. For the rest of the quarter, they laughed any time “not” was uttered and the guilty party would restate their point in a positive and clearer manner.

From a student perspective, hearing what *isn’t* led to only surface understanding of the concepts, which actually confused correlation with causation. Hearing what *is* led to deeper understanding of the concepts.

From my perspective as the instructor, explaining what *isn’t* led to students confusing correlation with causation. Explaining what *is* led to students correctly applying concepts to examples. From a feedforward perspective, the word NOT became a stimulus for my response of stopping. The pause became the stimulus for rephrasing our statement to avoid the word NOT and to state what “is.”