Researchers are engaged in finding the precursors for innovation. Drawing on Kirton's Adaption-Innovation (KAI) Inventory, we explicitly test Kirton's central premise that cognitive styles differentiate between preferences for producing ideas in a certain way. We argue that the generation of either a magnitude or original ideas is governed by different underlying cognitive styles. In a study with 191 individuals, we find that the cognitive style originality associates with ideational fluency whereas the rule governance style associates with the generation of original ideas. By providing a cognitive explanation for how ideas are generated, we deepen the understanding of the idea generation process. This is particularly important for the future use of the KAI and for organizations that strive to be innovative.