Cognitive dissonance is the uncomfortable feeling you get when you do or believe something that conflicts with your other beliefs or actions.
Examples:
Smoking: You know smoking is unhealthy, but you do it anyway and tell yourself it’s needed for relaxation.
Sustainability: You care about the environment but buy fast fashion and justify it by saying you’re trying to save money.
Procrastination: You know you should study for an exam but play video games instead, convincing yourself that you’ll study better later.