# decision-making

Affect Heuristic

When your feelings about something shape what you believe to be true about it.

Anchoring Bias

The first piece of information you encounter disproportionately shapes everything that follows.

Appeal to Nature

Arguing that something is good because it's natural, or bad because it's artificial - as though nature is always benign.

Arrival Fallacy

The belief that achieving a particular goal will make you permanently happy - followed by the discovery that it doesn't.

Attentional Bias

The tendency for your perception to be shaped by what you're already thinking about, worrying about, or primed to notice.

Availability Heuristic

We judge how likely something is based on how easily we can think of an example - not on how often it actually happens.

Bandwagon Effect

The tendency to adopt beliefs, behaviours, or trends because other people are doing so.

Base Rate Fallacy

Ignoring general statistical information in favour of specific but less reliable details about an individual case.

Betrayal Aversion

We'd rather face a worse outcome from chance than a better one that carries any risk of being betrayed by another person.

Chesterton's Fence

Before you remove something, make sure you understand why it was put there in the first place.

Circle of Competence

Knowing the boundaries of what you genuinely understand - and having the discipline to stay inside them when it matters.

Clustering Illusion

The tendency to see meaningful patterns in small clusters of random data, when the clusters are exactly what randomness looks like.

Complexity Bias

The tendency to prefer complex explanations over simple ones, and to mistrust simple solutions to problems that feel complicated.

Conformity Bias

The pull to adjust your beliefs, behaviours, or opinions to match those of the group around you.

Contrast Effect

The tendency for your judgement of something to shift depending on what you compare it to.

Manipulation Tactic

Dark Patterns

Deliberately deceptive design choices that trick people into doing things they didn't intend to do.

Decision Fatigue

The deterioration in the quality of decisions made by a person after a long session of decision-making, as mental energy depletes.

Effort Justification

The harder we work for something, the more we convince ourselves it was worth it - regardless of whether it was.

False Dilemma

Presenting only two options when more exist - forcing a choice between extremes and ignoring everything in between.

Systems Thinking

Feedback Loops

When the output of a system feeds back in as input, either amplifying or dampening the original effect.

First Principles Thinking

Breaking a problem down to its most basic truths and building up from there, rather than reasoning by analogy.

Rhetorical Device

Framing Effect

The way information is presented changes how we respond to it - even when the underlying facts are identical.

Functional Fixedness

The tendency to see objects, tools, and ideas only in terms of their conventional use, making it harder to find creative solutions.

Groupthink

When the desire for harmony in a group overrides honest analysis, leading to poor decisions nobody individually would have made.

Halo Effect

One positive trait colours your entire perception of a person, product, or idea.

Hanlon's Razor

Never attribute to malice that which is adequately explained by ignorance, carelessness, or incompetence.

Hasty Generalisation

Drawing a broad conclusion from too few examples - treating a small sample as though it represents the whole picture.

Hindsight Bias

The tendency to believe, after an event has occurred, that you knew it was going to happen all along.

Independent Evaluation

Forming your own judgement about an idea or claim before looking at what everyone else thinks.

Inversion

Instead of asking how to succeed, ask what would guarantee failure - then avoid those things.

Just-World Fallacy

The belief that people get what they deserve - that good things happen to good people and bad things happen to bad people.

Law of the Instrument

When all you have is a hammer, everything looks like a nail - the tendency to over-rely on a familiar tool or approach for every problem.

Loss Aversion

Losses feel roughly twice as painful as equivalent gains feel good.

Map is Not the Territory

Every model, theory, or description of reality is a simplification - useful, but never the whole picture.

Mere Exposure Effect

The tendency to develop a preference for things simply because you've encountered them before.

Psychological Defence

Motivated Reasoning

When we use reasoning not to find the truth, but to defend what we already believe.

Negativity Bias

The tendency for negative experiences, information, and emotions to affect us more strongly than positive ones.

Normalcy Bias

The tendency to underestimate the likelihood and impact of a disaster or major disruption because things have always been fine before.

Occam's Razor

When you have competing explanations for the same thing, the simplest one - the one with the fewest assumptions - is usually right.

Omission Bias

The tendency to judge harmful actions as worse than equally harmful inactions, even when doing nothing causes more damage.

Opportunity Cost

Every choice has a hidden price tag: the value of the next-best thing you gave up by choosing this one.

Optimism Bias

The tendency to overestimate the likelihood of positive outcomes and underestimate the likelihood of negative ones happening to you.

Post Hoc

Assuming that because one thing happened after another, the first thing caused the second - confusing sequence with causation.

Probabilistic Thinking

Thinking in terms of likelihoods and ranges of outcomes rather than certainties, so you make better decisions under uncertainty.

Psychological Defence

Rationalisation

Constructing a logical-sounding explanation for a decision or behaviour that was actually driven by emotion.

Salience Bias

The tendency to give disproportionate weight to prominent, vivid, or emotionally striking information while overlooking quieter details.

Second-Order Thinking

Thinking beyond the immediate consequences of a decision to consider what happens next - and what happens after that.

Self-Serving Bias

The tendency to credit your successes to skill and your failures to circumstances.

Slippery Slope

Arguing that one small step will inevitably lead to a chain of increasingly extreme consequences, without evidence that the chain is likely.

Social Proof

We look at what other people are doing to decide what we should do - especially when we're uncertain.

Status Quo Bias

The preference for the current state of affairs, where any change is perceived as a loss.

Sunk Cost Fallacy

Continuing to invest in something because of what you've already put in, not because of what you'll get out.

Survivorship Bias

Focusing on the people or things that succeeded while overlooking those that didn't - and drawing false conclusions from the incomplete picture.

Systems Thinking

Tragedy of the Commons

When individuals acting in their own rational interest collectively destroy a shared resource.

Systems Thinking

Unintended Consequences

Actions in complex systems produce outcomes nobody planned for - sometimes worse than the original problem.