The proposed research will tackle the big question of how belief in free will contributes to virtuous behaviors. Experimental research is beginning to demonstrate that belief in free will has a discernable impact on behavior. Moreover, societal interest in whether people have free will has increased in the past decade, in part due to increasing emphasis in psychology, medicine, and law on brain-based explanations for human behavior. We will use empirical methods to manipulate belief and disbelief in free will. The vast majority (7 out of 9) of our studies involve laboratory-based experimental methods, pioneered by Vohs & Schooler (2008), to manipulate free will belief. These include exposing people to persuasive arguments and having them mentally recite a series of evocative statements. We also will develop new lab-based methods to manipulate belief in free will. These experimental designs (that thus permit causal conclusions) will test a series of hypotheses about virtuous behaviors caused by believing in free will. Specific dependent measures include charitable donations (generosity), recycling and voting (prosocial participation), and keeping promises (dependability). We will assess mental processes caused by believing in free will, including willingness to delay gratification (future-mindedness) and learning from past mistakes. In addition, we will also explore interpersonal consequences, including increased gratitude. We expect at least five peer-reviewed articles to result from this project. These papers will be submitted to top journals in behavioral science and psychology. This project has the potential to fundamentally change the way that scientists and the general public think about belief in free will. As a result of the proposed work, a belief in free will will not be considered to be just a pesky illusion. We will show that belief in free will plays a powerful role in altering behavior toward ends that are good for individuals and society.