Conspiracy theorists may believe they are right because they have found information or evidence that supports their beliefs. They may also be influenced by cognitive biases, such as confirmation bias, which causes people to give more weight to information that confirms their existing beliefs and to discount information that contradicts them. Additionally, conspiracy theories can provide a sense of control and understanding in a complex and uncertain world, which can be appealing to some people.
Confirmation bias: A conspiracy theorist may be more likely to pay attention to and remember information that supports their beliefs, while disregarding or dismissing information that contradicts them. For example, if a conspiracy theorist believes that the moon landing was faked, they may focus on any evidence that seems to support this belief (such as inconsistencies in footage of the landing) while ignoring evidence that contradicts it (such as the overwhelming scientific evidence that the landing was real).
The illusion of explanatory depth: People often overestimate their understanding of complex systems, such as how governments or economies work. A conspiracy theorist may believe they understand the true workings of these systems, when in reality they only have a superficial understanding. They may also believe that their understanding is deeper than others, and that those who disagree with them are uninformed or misled.
The need for control: People often feel a sense of anxiety or uncertainty when they cannot explain or predict events. Conspiracy theories can provide a sense of control by providing explanations for otherwise mysterious or chaotic events. For example, a conspiracy theorist might believe that a major political event, such as 9/11, was orchestrated by a small group of powerful individuals, rather than being a tragic accident, as it provides them a sense of control over what happened.
Social identity: People often form their beliefs based on the opinions of the groups to which they belong. A conspiracy theorist may be more likely to believe in a conspiracy theory if it is endorsed by other members of their social group. They may also be more likely to reject information that contradicts the conspiracy theory if it comes from outside of their group.
Self-esteem: Conspiracy theories may be appealing to some people because they make the believer feel special or unique, as they have access to secret knowledge that others do not. They may also provide a sense of self-esteem, as it implies that the believer is more informed, skeptical and rational than others.
Books and academic studies as bases of this post:
"The Believing Brain: From Ghosts and Gods to Politics and Conspiracies - How We Construct Beliefs and Reinforce Them as Truths" by Michael Shermer
"Why People Believe Weird Things: Pseudoscience, Superstition, and Other Confusions of Our Time" by Michael Shermer
"The Conspiracy Theory Handbook" by Joseph Uscinski and Joseph Parent
"The Social Psychology of Conspiracy Theories" by Cristine Legare, Andre Souza, and Pascal Wagner-Egger.
"Conspiracy Theories: A Critical Introduction" by Mervyn Horgan