Informal Logical Fallacies and Cognitive Biases

Just like formal fallacies, both informal logical fallacies and cognitive biases are a threat to clear reasoning and argument. One can consult these for basic lists of informal fallacies and cognitive biases:

Bradley Dowden, “Fallacies,” Internet Encyclopedia of Philosophy.

“List of Fallacies,” Wikipedia.

“List of Cognitive Biases,” Wikipedia.

I. Informal Logical Fallacies In brief, informal fallacies can be divided into:

(1) Fallacies of relevance;
(2) Fallacies of defective induction;
(3) Fallacies of presumption;
(4) Fallacies of ambiguity (sophism)

A detailed list of the fallacies can be seen here:

(1) Fallacies of Relevance

Irrelevant Appeals

Appeal to emotion (argument ad populum)

Appeal to pity (argument ad misericordiam)

Appeal to Force (argumentum ad baculum)

Appeal to Authority (argumentum ad verecundiam)

Appeal to nature (argument from nature)

Appeal to Ignorance (argumentum ad ignoratiam)

Red herring fallacy

Irrelevant Conclusion (ignoratio elenchi)

Straw man argument

Ad Hominem Argument

Poisoning the well

Guilt by association

Naturalistic fallacy

Moralistic Fallacy

Argument from silence (argumentum ex silentio)

Genetic fallacy

Gambler’s Fallacy

Tu quoque

(2) Fallacies of defective induction

Argument from Ignorance (ad ignorantiam)

Appeal to Inappropriate Authority (ad verecundiam)

False cause

Hasty generalization

Faulty generalization

Other inductive fallacies

Slothful induction

Overwhelming exception

Biased sample

Misleading vividness

Statistical special pleading

(3) Fallacies of presumption (fallacies of illegitimate presumption)

Complex question

False cause

Begging the question

Accident

Converse accident

No True Scotsman Fallacy (fallacy of ambiguity and presumption)

(4) Fallacies of ambiguity (sophisms)

Fallacy of equivocation

Fallacy of amphiboly

Fallacy of accent

Fallacy of composition

Fallacy of Division

Other fallacies relevant to economics include the following:

(1) Paradox of thrift/saving
(2) Paradox of costs
(3) Paradox of debt
(4) Paradox of liquidity
(5) Paradox of tranquillity (Minsky).

II. Cognitive Biases
In modern psychology, an important theory about how we make decisions under uncertainty is the “heuristic and biases” method of Tversky and Kahneman (1974; Kahneman et al. 1982). This posits that human being use heuristics, which are short cuts to solve problems that are not always reliable, and that we are subject to cognitive biases that might impair the success of our decisions. As I have said previously, the modern Post Keynesian theory of subjective expectations can use these theories and focus on how cognitive biases influence the investment decision and how investment fluctuates.

The classification of cognitive biases is below:

(1) Decision-making and Behavioural biases

Anchoring

Attentional Bias

Bandwagon effect

Bias blind spot

Choice-supportive bias

Confirmation bias

Congruence bias

Contrast effect

Denomination effect

Distinction bias

Endowment effect

Experimenter’s or Expectation bias

Focusing effect

Framing effect

Hostile media effect

Hyperbolic discounting

Illusion of control

Impact bias

Information bias

Irrational escalation

Loss aversion

Mere exposure effect

Money illusion

Moral credential effect

Negativity bias

Neglect of probability

Normalcy bias

Omission bias

Outcome bias

Planning fallacy

Post-purchase rationalization

Pseudocertainty effect

Reactance

Restraint bias

Selective perception

Semmelweis reflex

Social comparison bias

Status quo bias

Unit bias

Wishful thinking

Zero-risk bias

(2) Biases in probability and belief

Ambiguity effect

Anchoring effect

Attentional bias

Availability heuristic

Availability cascade

Base rate neglect or Base rate fallacy

Belief bias

Clustering illusion

Conjunction fallacy

Forward Bias

Gambler’s fallacy

Hindsight bias

Illusory correlation

Observer-expectancy effect

Optimism bias

Ostrich effect

Overconfidence effect

Positive outcome bias

Pareidolia

Pessimism bias

Primacy effect

Recency effect

Disregard of regression toward the mean

Stereotyping

Subadditivity effect

Subjective validation

Well travelled road effect

(3) Social biases

Actor–observer bias

Dunning–Kruger effect

Egocentric bias

Forer effect (aka Barnum effect)

False consensus effect

Fundamental attribution error

Halo effect

Illusion of asymmetric insight

Illusion of transparency

Illusory superiority

Ingroup bias

Just-world phenomenon

Moral luck

Outgroup homogeneity bias

Projection bias

Self-serving bias

System justification

Trait ascription bias

Ultimate attribution error

(4) Memory errors

Cryptomnesia

Egocentric bias

False memory

Hindsight bias

Reminiscence bump

Rosy retrospection

Self-serving bias

Suggestibility

Telescoping effect

Von Restorff effect

III. Cognitive Closure?There are some philosophers like Colin McGinn and even Noam Chomsky who claim that human beings are subject to a phenomenon called cognitive closure, the belief that certain problems are insolvable, and that our minds are “closed”: that our minds are subject to cognitive limitations such that we cannot begin to understand certain ideas and concepts, or solve some problems. The mind-body problem, identity, and free will might be such problems:

“We … [sc. suffer] from what I call ‘cognitive closure’ with respect to the mind-body problem. Just as a dog cannot be expected to solve the problems about space and time and the speed of light that it took a brain like Einstein's to solve, so maybe the human species cannot be expected to understand how the universe contains mind and matter in combination.” (McGinn 2002: 182).

I wonder whether the problem of induction might be added to the list? (although many philosophers might argue that it has in fact been solved: there is no rational justification for it).

However, other philosophers disagree with the “cognitive closure” thesis. Daniel Dennett presents a good case against it in Darwin’s Dangerous Idea: Evolution and the Meanings of Life (London, 1996) pp. 381–383. In essence, Dennett thinks that language makes the difference: as is well known, there are in principle an infinite number of meaningful sentences that could be constructed in any natural language. There is, he thinks, a set of possible sentences that best describe the solution to the mind–body problem, and why could we not understand that set of propositions? If the problem is solvable, then it could be explained in natural language. Although Dennett does not rule out the possibility of ‘cognitive closure,’ he concludes that there is “no evidence of the reality or even likelihood of ‘cognitive closure’ in human beings” (Dennett 1996: 382). That appears to be good news for the power of the human mind and human reason!


BIBLIOGRAPHY

Copi, I. M., Cohen, C. and K. McMahon. 2011. Introduction to Logic (14th edn), Pearson Education, Upper Saddle River, N.J. and Harlow.

Dennett, D. C. 1996. Darwin’s Dangerous Idea: Evolution and the Meanings of Life, Penguin, London.

Kahneman, D., Slovic, P. and A. Tversky (eds), 1982. Judgment Under Uncertainty: Heuristics and Biases, Cambridge University Press, Cambridge.

McGinn, C. 2002. The Making of a Philosopher: My Journey Through Twentieth-Century Philosophy, HarperCollins, New York.

Tversky, A. and D. Kahneman, 1974. “Judgment under Uncertainty: Heuristics and Biases,” Science (American Association for the Advancement of Science) 185 (4157): 1124–1131.