In this article I discuss how false memories do not always have to be associated with negative outcomes. Indeed, under some circumstances, memory illusions, like other illusions more generally, can have positive consequences. I discuss these consequences in the context of the adaptive function of memory, including how false memories can have fitness-relevant benefits for subsequent behavior and problem solving. My hope is that this article changes how illusions are conceptualized, especially those arising from memory. Rather than being a "demon" that vexes our theories of memory, illusions can be thought of as sometimes having positive consequences much in the same way as many of the other outputs of a very powerful, adaptive memory system.