Why so radical? Nature, causes, and consequences of radical belief systems.

Over the past three decades, radical left- and right-wing parties have re-emerged as pivotal electoral forces across Europe. This dissertation aims to contribute to the literature by providing new insights into the nature, the causes, and the consequences of radical belief systems through achieving five objectives: (1) Exploring the constitutive elements of radical belief systems and understanding how particular configurations of these elements result in different types of radicalism; (2) investigating the roots of radical belief systems by investigating the causes of people’s adherence to radical ideas; (3) studying the consequence of endorsing radical ideas by focusing on how the different components of radical beliefs relate to the propensity to vote for left- and right-wing radical parties; (4) understanding for what reasons radical individuals hold more or less extreme policy opinions and negative leader evaluations; (5) examining how radical individuals (a) position themselves towards liberal democracy and (b) instrumentally and conditionally adhere to particular democratic liberties.