There are a number of very helpful, but often underutilized, principles and procedures that can augment decision making in clinical and legal settings. Psychologists often restrict their range of decision-making strategies and options--at the cost of maximizing diagnostic and predictive accuracy--in part as the result of "ontological-epistemological one-worldedness" (O-E O-W). However, no philosophical, logical, or scientific necessity demands strict consistency between views regarding the nature of psychological phenomena and views about how to best assess or learn about those phenomena. Relaxing this unnecessary and largely psychologically-based O-E O-W may promote greater comfort with and utilization of the methods that are discussed in this article for increasing judgmental accuracy.