Alright kiddo, let's dive into the funky world of Psychology, featuring our main star today, the 'Cognitive Dissonance Theory' by a cool guy named Leon Festinger. Get ready to ride the rollercoaster of inconsistent beliefs, ideas, and actions. Trust me, it's as exciting as it sounds!

Cognitive Dissonance is like that feeling you get when your math homework doesn't add up, except it's about your beliefs or ideas. You know, those times when two of your beliefs are having a wrestling match in your head, or when your actions are dancing out of tune with your beliefs, or when new information gatecrashes your beliefs party. All these situations cause mental stress, just like that awful math problem!

An individual feeling this inconsistency (a.k.a. "dissonance") gets as stressed as a cat in water and wants to reduce this dissonance. Imagine you promised your best friend you'd attend their party but also told your mom you'd help her with chores. Your choices? Either you change your behaviour (skip the party) or change your belief (convince yourself chores can wait). This is just like choosing the lesser evil in an "Are you a cake or ice cream person?" debate.

We all love to think that our beliefs drive our behaviour, but surprise! Most of the time, it's the other way around. Just like a bumpy road can change a smooth car ride, behaviour often steers our beliefs.