Conspiracy theories have gained popularity in recent years. Especially in recent years, conspiracy theories reached a worldwide high. An example: the earth is flat. Various social media networks are widely accessed by followers to spread their beliefs. In the following paper, we address the question: “How do the Flat Earthers justify their conspiracy theory and how do they try to spread this worldview via the social media platform ‘X’?” The basis of the work is the theory of critical rationalism according to Karl Popper. As a method of investigation, a media and content analysis was conducted with several accounts of the social media network ‘X’ (formerly known as Twitter) examined for this purpose. In summary, the results can be interpreted as follows: The logic of the Flat Earthers is primarily vague or non-existent, and scientific foundations are also unfounded. Conspiracy theorists try to reach as many people as possible via the social media algorithms and this is usually only moderately successful.