Rationalisation Bias

Rationalization is a defence mechanism (ego defence) in which people justify difficult or unacceptable feelings with seemingly logical reasons and explanations. For example, a student who is rejected from her dream college may explain that she's happy to be attending a school that's less competitive and more welcoming. The same is with the tale of the Fox and the sour grapes too.

Apparent logical reasons are given to justify behaviour that is motivated by unconscious instinctual impulses. It is an attempt to find reasons for behaviours, especially one's own. Rationalizations are used to defend against feelings of guilt, maintain self-respect, and protect oneself from criticism.

Rationalization encourages irrational or unacceptable behaviour, motives, or feelings and often involves ad-hoc hypothesizing. This process ranges from fully conscious (e.g. to present an external defence against ridicule from others) to mostly unconscious (e.g. to create a block against internal feelings of guilt or shame). People rationalize for various reasons—sometimes when we think we know ourselves better than we do. Rationalization may differentiate the original deterministic explanation of the behaviour or feeling in question.

We can take an extreme example here and say an abuser and a victim both have their own internal rationalisation on why they deserve what they did to the other or got from the other, as the case maybe, and justify the same using this bias present in their minds. Both of them could offer seemingly justified explanations and reasons as per their mind and try to convince the other side that it is something that had to happen and there is nothing wrong in what happened. Stockholm Syndrome could be one other example for extreme internal rationalisation for both the abuser and the victim and both the parties seem to justify their respective actions using this bias and so are justifications offered by both sides in toxic relationships be it friendship, marriage, family, colleagues, etc. One must be very careful when Rationalisation Effect is at play.