What makes an idea great? Novelty helps. But so does practicality--you want to be able to put it into practice. Strike a balance somewhere in the middle and you might just have a winner. 

That's why Justin M. Berg, a Ph.D. candidate at The Wharton School, University of Pennsylvania, wanted to learn how to incorporate both important traits into new ideas. His recent study, "The primal mark: How the beginning shapes the end in the development of creative ideas," suggests that different stimuli have a notable impact on the innovation process. 

Berg called the stimuli "primal marks." In his paper, he explained that the term is borrowed from painting theory. "The concept is that the first brush stroke a painter makes on a blank canvas, known as the primal mark, is especially important because it shapes what the painter subsequently paints on the canvas," Berg writes.

He set up an experiment that tested the way two different types of stimuli--which he called "familiar" and "new"--influenced participants' brainstorming.

Berg told 185 university students that the university bookstore was looking to add a new innovative product to its inventory. One group of participants was shown a picture of a cork board, which was the familiar primal mark, and the other was shown a picture of a fishing pole, the new primal mark. Both groups of students were asked to incorporate at least one element of the pictured item in their solution.

Nine judges, including three managers from the actual bookstore, were recruited to rate the ideas on a seven-point scale. They judged students' responses on both their novelty and usefulness.

In the end, Berg concluded that the novel stimulus did indeed lead to ideas that were more creative--with an average rating of 3.82 out of seven. This compared to ideas that were inspired by a conventional stimulus--which received an average rating of 3.05.  

However, the novel stimulus also resulted in products that were less useful. Ideas derived from a novel primal mark received a usefulness rating of 3.65 compared to 4.06, which was the average rating for ideas that came from the familiar primal mark.  

So what's the upshot? Berg said the results suggest that in order to come up with an idea that achieves a tradeoff between novelty and usefulness, the primal mark has to offer a balance as well. In other words, employees need exposure to both the practical and the absurd to find the sweet spot for that one killer idea.