This meme shows the meaning of cognitive dissonance. People when told information about or against their beliefs,they either change their belief or make excuses as to why that cannot be true.
This woman is cheering to those that can change their beliefs if given information that actually changes their thought process on the belief. The hope of changing old or worn out beliefs is there. Some cannot change their belief system even when proven wrong to them. These people will make reasons or problems to keep their belief in place.