A new model is allowing scientists to explore how changing an individual's certainty in the belief on the truth of one statement leads to changes in their beliefs on the truth of others. This tool could help to answer questions about individuals' likelihoods of being persuaded to a new belief. People rarely form opinions by merely accepting or rejecting the social consensus of others, studies have shown. For example, individuals who reject evolutionary theory and manmade climate change may be aware of the scientific consensuses on these subjects, but reject the ideas anyway, as other, complex social and environmental factors influence their ultimate opinions. Here, using a model designed to represent social influence among individuals with multiple beliefs, Noah Friedken and colleagues provide a step toward understanding this phenomenon. Their work extends the so-called Friedkin-Johnson model, which explores how individuals form opinions in complex circumstances, by better accounting for the power of underlying beliefs (for example, the belief that human civilization is too insignificant to alter the global environment, which may prevent someone from believing in manmade climate change). Friedkin and colleagues incorporate an "intrapersonal" influence mechanism in their modeling framework, in which acceptance of one proposition influences the acceptance of others. Using this framework, the researchers performed a theoretical test that looked at what happened when beliefs regarding the trustworthiness of evidence on the existence of weapons of mass destruction in Iraq changed in the U.S., and how that in turn impacted views on whether the invasion of Iraq was justified. They characterized how beliefs, either held by a few or many, can influence interpersonal networks. The work is further explored by Carter Butts in a related Perspective.