The term 'ideas-informed society' describes democracies in which citizens believe in the value of staying well-informed and up-to-date with current affairs. They also put these beliefs into action: critically engaging with new ideas and perspectives, delving into scientific discoveries or emerging technologies and exploring aspects of history and culture. Likewise, they stay abreast of political, economic and health-related events, new products, new forms of media and so on. While ideas engagement can, in theory, lead to citizens becoming better informed, better able to engage in effective decision-making and better able to understand the world around them, these benefits do not reach everybody. Likewise, in the ideas ecosystem generally, we can often see 'dark' ideas winning through: resulting in less optimal outcomes for both citizens and nations. While interest in the notion of the ideas-informed society is burgeoning, we argue that, if future research is to be effectively positioned to support meaningful ideas engagement, what is now required is a theoretical frame to guide this research moving forward. We use this paper to argue for such a framework based on three principal elements: (1) whether individuals possess a prospective mindset, enabling them to value ideas engagement, as well as become more likely to commit to behaviours concomitant with ideas that have optimal and wide-reaching outcomes; (2) the features of individuals' social networks, and how these impact on citizens' access to ideas and the nature of their ideas engagement; and (3) individuals' levels of education and the extent to which the education people receive allows them to engage with ideas critically. As well as setting out the case for our proposed framework, we conclude by proposing future research to enable us to further specify and verify this framework as well as develop instruments to test it nationally and internationally.