[BroJoeK]

Cognitive dissonance is said to result from some anomaly which seems to contradict what I thought was true.
But many people are oblivious to such anomalies and others quickly rationalize them away.

Careful study of a new anomaly and how it might affect previous understandings is one of the purposes of science, and I suspect a high-point in many scientific careers.

[reasonisfaith]

A good example of cognitive dissonance is if I encounter evidence supporting the truth of evolution, against the background of my basic desire that evolution be false.

Another good example of cognitive dissonance is if you encounter evidence refuting the truth of evolution, contradicting your wish that evolution be true.