No evidence for an assumption of a theory can be gained by data derived from methods dependent on that theory. Three experiments, using methods independent of psychoanalysis, test the psychoanalytic posit that primary process exists as a formal mental mode distinct from secondary process. The three experiments, using a nonpsychoanalytic index for primary process, test for a preponderance of primary process organization in three areas in which Freud observed primary process: (1) in unconscious mental states and during implicit tasks; (2) in the mental productions of preschool children; and (3) in anxiety states, as these are typically associated with unconscious conflict. All three experiments show significant results in favor of the primary process. Further, the three experiments taken together, because they account for seemingly disparate data, lend further credence to the original assumption. These positive results suggest that primary process may be more important than even Freud suspected. Perhaps it is the basic mental organization in many nonhuman mammals and some birds. Primary process organization may also underlie aspects of such basic psychological operations as generalizations in conditioning and assessments-in-action, as opposed to judgments proper, about how one would act. Finally, primary process may play a key role in drive activity. Three types of experiments are proposed to test these far-reaching applications of the primary process concept.