@TheMadPirate @Sage @Wehrmacht > Cognitive Dissonance just means that the person is trying to hold in his head two contradictory arguments at the same time
Cognitive dissonance is the condition created by being unable to reconcile two contradictory ideas; it's not the ideas themselves. People believe contradictory things all the time, but it doesn't tend to gnaw at them.
> solipsism ( the idea that the self is the only real existence ) to be used to describe behaviors associated to the original meaning of selfishness
It's still misuse of the term, which starts with the premise that you cannot be certain of any other consciousnesses because you have only your own observations, and they are filtered through your consciousness. "Solipsism" isn't selfishness, it's "For all I know, I'm a brain in a jar or I'm hallucinating and none of this is real." You can be certain you exist, but you have only your own perceptions (which may not be real) to prove that I exist. That's solipsism, it's got nothing to do with selfishness. That's why things like this:
> since given that a solipsist believes only his existence matters
are incorrect. "What matters" and "what you know to be true" are different.