a logical alternative used to mask the real reason
Rationalization is the attempt to have your cake and eat it too. When a character expects that catering to his desires will bring about some cost or punishment, he tries to do what he'd like in a way he thinks will avoid retribution. One way is to come up with an excuse. Rationalization involves fabricating an artificial reason for one's attitude or actions that will excuse them. The reason must make sense as being a possible actual cause of the character's activities. In fact, it might very well have been the reason, except that it wasn't, which is what makes it a Rationalization.
syn. fabricated excuse, ulterior explanation, false justification, artificial reason