This Element deals with the relationship between cognition, understood as the process of acquiring and developing knowledge, and diverse types of conspiracy theories, or short, 'CTs'. Section 1 lays the groundwork for the analysis by determining four components of narrative argumentative framing in CTs, of which the first three are constitutive for all CTs, with a fourth representing the 'optional' collective action-guiding “scenario” component. Section 2 exemplifies manifestations of these components by discussing contemporary and historical 'hoax' and 'asserting' CTs and 'empowering' CTs. Section 3 takes a cognitive-evolutionist and pragmatic view at the conditions for the 'success' of CT scenarios. In conclusion. Section 4 formulates lessons for countering the effects of socially detrimental CTs by deconstructing them and by obstructing their dissemination.