From Understanding Arguments by Walter Sinnott-Armstrong and Robert Fogelin, which I use in my critical thinking course:
Ideologies and worldviews tend to be self-sealing. The Marxist ideology sometimes has this quality. If you fail to see the truth of the Marxist ideology, that just shows that your social consciousness has not been raised. The very fact that you reject the Marxist ideology shows that you are not yet capable of understanding it and that you are in need of re-education. This is perfect self-sealing. People who vigorously disagree with certain psychoanalytic claims can be accused of repressing these facts. If a boy denies that he wants to murder his father and sleep with his mother, this itself can be taken as evidence of the strength of these desires and of his unwillingness to acknowledge them. If this kind of reasoning gets out of hand, then psychoanalytic theory also becomes self-sealing and empty. Freud was aware of this danger and warned against it. […]
[This kind of argument can] counter criticism by attacking its critics. Critics of Marxism are charged with having a decadent bourgeois consciousness that blinds them to the facts of class conflict. The critic’s response to psychoanalytic theory is analyzed (and then dismissed) as repression, a reaction formation, or something similar. Here self-sealing is achieved through an ad hominem fallacy. We might call this self-sealing *by going upstairs*, because the theorist is looking down on the critic.
Much of this will be familiar from Hannah Arendt’s criticism of totalitarian ideology.
Notably, many arguments for evolutionary psychology have a similar form, especially those that focus on the way beliefs are formed to signal loyalty or attract esteem.
Second Opinions