Definition: Occurs when a person attempts to show one's argument is flawed by mentioning things about the person to justify why they are wrong.
Example: Refuting an argument by accusing the arguer of bias, or of claiming that the arguer stands to profit from others accepting the argument.
Insight: Even those you dislike or believe things that you believe to be untrue might be right about some things that you are wrong about.
Insight: Arguments stand or fall based on whether its premises support its conclusion, not on the personal characteristics, motives, history, or other beliefs of the person making the claim.
Insight: No argument is refuted by demonstrating the flaws or biases of the person making the argument.
Insight: The ad hominem fallacy does not apply to testifying in court as testifying is not arguing. It is reasonable to question the motives or character of someone who is testifying, and testimony stands or falls on whether the claims made are believable.
Insight: The bias of the arguer is irrelevant to whether premises support the conclusion.
Insight: To refute an argument you need to show that evidence is insufficient, based on false assumptions, that evidence is irrelevant, that evidence has been omitted, or that improper weight has been given to pieces of evidence.
Principle: Don't reject an argument on the basis of the person making it.
Reference: Paul Slovic proposed the affect heuristic - people let likes and dislikes determine their beliefs.
Insight: The affect heuristic can hinder our ability to see the negatives in our own position, and the positives in the position of others (particularly opponents).
Reference: Dan Ariely: experiments related to arbitrary coherence demonstrate how the power of suggestion (anchoring) combined with our tendency to want to appear consistent leads to decisions that are coherent with the initial anchor. We are irrational.
Insight: Once we make decisions based on a price, it will impact future decisions (anchoring).
Insight: The implication of arbitrary coherence is that it calls into question the benefits of a free market. If we can be manipulated to value things arbitrarily, then it is the manipulating actors that stand to benefit from free trade. Traditional economics assumes humans are rational, but arbitrary coherence suggests that our market behaviour is more irrational than rational.
Definition: The tendency to make judgements by the ease with which ideas come to mind.
Example: Teachers improving course feedback ratings by asking students to name ten ways the course could be improved instead of two. Since it is more difficult to come up with ten ways from the mind, students rated the course more favourably.
Insight: If something is easily retrieved from memory, it will be judged to be more prevelant or large.
Insight: We often substitute facts with impressions about how easily something comes to mind.
Reference: Amos Tversky and Daniel Kahneman defined the concept. In was born out of the thought about what people actually do when they estimate the frequency of something.
Reference: Paul Solvic, Sarah Lichtenstein, et al: people's judgements about the frequency of death from various causes is biased by the media, which focuses on drama, novelty, or location.
Insight: Information overload can hinder our ability to make sound judgements.
Insight: Considering the few important factors can lead to more effective decision making.
Insight: More variables to consider in decsion making makes it more likely that we give more weight to unimportant variables, and less weight to important ones.
Reference: Kaheman and Tversky in naming the Conjunction Fallacy.
Definition: Referred to as the Forer Effect. The tendency of people to accept vague and general personality descriptions as relating to them specifically.
Insight: Common explanations for this effect include hope, wishful thinking, vanity, and the tendency for humans to want to pattern match or make sense of things.
Reference: Bertram R. Forer: the psychologist found that people believed that general personality descriptions were unique to them.
Reference: Psychologist Barry Beyerstein: "hope and uncertainty evoke powerful psychological processes that keep all occult and pseudoscientific character readers in business."
Definition: The tendency to see the behaviour of others as personal characteristics without considering the situation.
Reference: Lee Ross: social psychologist coined the term.
Definition: A bias where the perception of a positive (or negative) trait in people or products influences our further judgement of those things.
Example: The belief that good looking people are intelligent or kind.
Example: When we buy products because of the brand.
Insight: Our impression of company performance often greatly influences our judgement of company strategy or the management.
Insight: Advertisers take advantage of the halo effect by using famous or good looking people.
Reference: The term 'halo effect' was used by Edward Thorndike in 1920 to describe how commanding officers rated their soldiers. If a solider made a good or bad first impression, it would dramatically impact the officer's judgement going forward.
Definition: The tendency to construct memories according to currently known facts and current beliefs.
Example: Saying "I knew it all along" when you probably didn't.
Example: The tendency of believers of prophecies to retrofit events to past claims.
Example: The tendency of people to think they can explain events after they happened.
Insight: We often construct memories from present beliefs rather than what was true in the past.
Insight: Events can easily be explained after the fact.
Insight: Our brains are pattern matching machines. Once we know something to be true, our minds start to reconstruct the past so that our memories fit what happened.
Insight: Hindsight bias may lead people to be overconfident in their ability to predict the future.
Principle: Don't always rely on memory.
Insight: It can feel good to believe we are in control.
Insight: Just because we feel good when we think we are in control, it does not mean that we are actually in control.
Insight: Uncertainty, or the feeling that we are not in control leads to anxiety. Anxiety is something that most people try to avoid.
Insight: The illusion of control can drive us to try things and accomplish that which we might not otherwise.
Insight: The illusion of control can be good in some situations, unless it leads to delusion that harms ourselves or others.
Definition: Less is more.
Reference: Named after English philosopher William Ockham (1285-1349).
Reference: In Latin it is read as: Pluralitas non est ponenda sine neccesitate "plurality should not be posited without necessity", meaning always do not make things more complex unless needed.
Reference: Often used in debates (by both sides) about the existence of God.
Insight: The fewer assumptions made, the fewer questionable assumptions there will be.
Insight: Also known as the principle of parsimony (being economical with resources), to mean "the simpler the explanation the better".
Insight: Occam's razor today is used as heuristic advice: more often than not, a theory that requires more or more complex assumptions will usually be wrong.
Definition: Plans and forecasts that are unrealistically close to best-case scenarios.
Principle: Research similar completed tasks.
Definition: The tendency to believe that trends, patterns, and information that we have observed in the recent past will continue in the future.
Insight: The very recent past can be a relatively good predictor of the short term future, but is not a good predictor long term in many fields.
Insight: Recent events and trends are often easier to remember, so recency bias is also related to availability bias (how readily events or pieces of information come to mind, influencing our decisions, behaviour, or feelings).
Insight: The straw man fallacy violates the principle of fairness.
Insight: A straw man argument is where one attacks a distorted version of another person's argument, a position created rather than the actual position of the opponent.
Insight: Straw man arguments can appear strong to 3rd party observers that are unfamiliar with the topic.
Insight: Using straw man tactics can result in preventing a serious debate on the issue at stake.
Insight: Straw men can appear in debates because of ignorance (not understanding the actual position of the opponent), incompetence, or indifference to the truth (where the goal is just to look good or 'win').
Principle: When attempting to refute an argument, refute the strongest version of the position, not a weaker or distorted version.