Cognitive Dissonance & Bias – Comprehensive Notes

Core definition - Psychological tension experienced when your thoughts, feelings, and behaviours do not match up.
- Think of it formally as: ext{Cognitive Dissonance}= ext{Psychological Tension}( ext{Thoughts}\neq\text{Feelings}\neq\text{Behaviours})
Tri-component model reminder - This tension happens when the affective (feelings), behavioural (actions), and cognitive (thoughts/beliefs) parts of you are inconsistent.
Decision-making illustration - Imagine having to choose between a dream job overseas and staying close to your family. No matter what you pick, you'll sacrifice something, leading to tension.
Dog-waste example - You forget bags for your dog and leave a mess. Later, you feel guilty and worried. To reduce this dissonance, you might tell yourself, “It’s only once; others do it too.”
Smoking example - If you believe “smoking harms health” (thought), feel bad about it (feeling), but keep smoking (behaviour), you'll constantly feel this tension.

Definition - These are systematic, often unconscious, ways our brains interpret information non-objectively. They act as psychological defences to reduce the discomfort of cognitive dissonance.
Why they emerge - Our brains naturally seek order and consistency, so when there’s a conflict, they quickly create mental shortcuts to make things feel coherent again.

Confirmation Bias

Definition - The tendency to look for, prefer, and recall information that supports what you already believe, while ignoring anything that contradicts it.
How it avoids dissonance - By finding lots of evidence that supports your existing belief, you can trick yourself into thinking your beliefs and actions are perfectly aligned.
Vaccination example - If you already believe “vaccines are dangerous,” you might only read websites and forums that support this view, ignoring scientific research. Social media can make this worse by showing you only content you agree with.

Actor–Observer Bias

Definition - We explain our own actions by blaming external situations, but we explain other people’s identical actions by blaming their personal traits.
How it avoids dissonance - By putting the blame for our mistakes on external factors, we protect our self-image and feel less tension.
Coffee-spill example - If you spill coffee, you might say, “The mug was slippery” (a situation). But if a coworker spills coffee, you might think, “They’re clumsy” (a trait about them).

Self-Serving Bias

Definition - Taking credit for your successes (attributing them to your skills) but blaming failures on outside circumstances.
How it avoids dissonance - Success feels good (no tension). When you fail, you blame things like the weather or a difficult test, which stops you from feeling bad about yourself.
Soccer/Exam examples - Scoring a winning goal: “I’m so talented!” Missing a goal: “The pitch was slippery.” Passing an exam: “I'm smart.” Failing an exam: “The test was unfair.”

False-Consensus Bias

Definition - Overestimating how much other people share your beliefs and behaviours.
How it avoids dissonance - If you believe most people agree with you, you feel more normal and less conflicted about your own views or actions.
Environmental activism example - You might assume all young people are as passionate about environmental issues as you are, which makes your own efforts feel more validated.

Halo Effect

Definition - When one positive quality (like being physically attractive) leads you to have an overall positive impression of someone.
How it avoids dissonance - This bias makes you overlook negative or contradictory qualities, helping you maintain a simple, positive view of the person.
Dating example - An attractive partner might have a criminal past or a habit of stealing, but because of their attractiveness, you still see them as “ideal.”

Cognitive dissonance is the uncomfortable feeling when your thoughts, feelings, and actions don't match.
The main way people deal with this discomfort is by using cognitive biases:
- Confirmation Bias
- Actor-Observer Bias
- Self-Serving Bias
- False-Consensus Bias
- Halo Effect

Heuristics — these are mental shortcuts, different from biases, but often related to how we think (we'll cover them next).