Previously, I’ve written about the IKEA effect and “not invented here” (NIH) syndrome, which causes people to place less value on ideas proposed by someone else and more value on ideas they generate themselves. As I wrote in that post, “in the case of serious NIH syndrome, the best case scenario is that the audience believes your ideas are actually their own.”
As it turns out, a recent study (reported by BPS Research Digest) confirmed this directly. In several experiments, some of the participants were asked to imagine that they had a theory about the relationship between two fictional creatures on a fictional planet (i.e., that Niffites were predators and Luupites were their prey) while others were asked to imagine that someone named Alex had this theory (or that no one in particular had it).
Then the participants were given a series of seven facts that appeared to either support or oppose the theory (e.g., that Niffites are larger than Luupites, or that Luupites have sharper teeth than Niffites, respectively). Even though the theory wasn’t really the participants’ own theory, those who had been told that it was more stubbornly persisted in believing it in the face of opposing evidence than those who had been told it was Alex’s (or no one’s).
Thus, if you can get the audience to believe that your ideas are theirs, they’ll feel more invested in them and be more likely to believe them.