Sympathetic Resonance or Sympathetic Vibration is a harmonic phenomenon wherein a formerly passive string or vibratory body responds to external vibrations to which it has a harmonic likeness. The classic example is demonstrated with two similar tuning-forks of which one is mounted on a wooden box.
According to The New Grove Dictionary of Music and Musicians:
The property of sympathetic vibration is encountered in its direct form, in room acoustics, in the rattling of window panes, light shades and movable panels in the presence of very loud sounds, such as may occasionally be produced by a full organ. As these things rattle (or even if they do not audibly rattle) sound energy is being converted into mechanical energy, and so the sound is absorbed. Wood paneling and anything else that is lightweight and relatively unrestrained have the same effect. Absorptivity is at its highest at the resonance frequency, usually near or below 100 Hz.
Basically cognitive resonance would be the opposite of cognitive dissonance theory...
In A Theory of Cognitive Dissonance (1957), Leon Festinger proposed that human beings strive for internal psychological consistency to function mentally in the real world. A person who experiences internal inconsistency tends to become psychologically uncomfortable and is motivated to reduce the cognitive dissonance. They tend to make changes to justify the stressful behavior, either by adding new parts to the cognition causing the psychological dissonance or by avoiding circumstances and contradictory information likely to increase the magnitude of the cognitive dissonance.
Coping with the nuances of contradictory ideas or experiences is mentally stressful. It requires energy and effort to sit with those seemingly opposite things that all seem true. Festinger argued that some people would inevitably resolve dissonance by blindly believing whatever they wanted to believe.
Festinger, L. (1957). A Theory of Cognitive Dissonance. California: Stanford University Press.
Human beings strive for internal psychological consistency. By providing psychological consistency that is in key or in ‘harmony’ we find resonance. This is why children are taught with the words peace and harmony.
In a grand symphony -- everything sounds off if anyone breaks unison.
We had to abide by the king/queen/dictator/ruler/lord/narcissistic-oppressor-in-chief
Luckily life is more like jazz -- we as the instrumentalist have control over what we play.
We are free.
Yet even in a jazz duo, we see that one instrumentalist and the other must agree upon a key for the song. Everything else is raw vibration, emotion and feeling elicited to sound. Perhaps Leon never got to listen to any jazz records...
After coming to understand this I would argue that people should resolve dissonance by seeking the truth instead of believing what they want.
I would further argue for them to seek resonance because the question begs to be asked:
If cognitive dissonance leads to stress, does cognitive resonance lead to bliss?