Fallacies

A fallacy is a recurring form of error in reasoning — a mistake common enough, and structured enough, to be worth naming so that it can be recognised on sight. This page indexes the fallacies identified on this wiki, and distinguishes the ones Objectivism adds to the traditional list from the ones it inherits.

Two kinds of error

Traditional logic catalogues errors in inference: cases where the conclusion does not follow from the premises, or where something irrelevant is offered in place of an argument. Those apply whatever one's philosophy, and Objectivism uses them unchanged. See Logic and Logical Terms.

Objectivism adds a second category, which is its distinctive contribution here: errors in concept-formation. These occur before any inference is drawn, in the terms themselves. A person reasoning validly from a concept that was never properly formed will reach a conclusion that is internally impeccable and about nothing.

The reason a whole class of errors lives at this level is that conceptual knowledge is hierarchical. Concepts are built from earlier concepts, and each stands on the ones below it. See Hierarchy, Concept formation and Introduction to Objectivist Epistemology. A defect low in the structure is invisible from the top and undoes everything above it.

Conceptual fallacies

Floating Abstraction: Using a concept without knowing what concretes it stands for — a word taken over from other people and never connected to the perceptual evidence that would give it meaning.
Fallacy of the stolen concept: Using a concept while denying the more fundamental concepts it depends on. Self-eliminating rather than merely false, since the denial has to be stated in the terms it destroys.
Frozen Abstraction: Substituting one particular concrete for the wider abstraction that subsumes it — treating altruism as though it were the whole of morality, so that the only question left is which version to adopt.
Package-Deal: Packing under one term things that differ in nature, truth-status or value, so that accepting the word smuggles in the association.
Invalid Concept: A term that names no legitimate concept at all, because the alleged units share no defining characteristic — including the anti-concepts coined to displace a valid term.
Reification of Zero: Treating "nothing" as a kind of something — a special existent with properties of its own.
Rewriting Reality: Treating the metaphysically given as though it were open to choice, or a man-made fact as though it were unalterable.

A related rule, which is what several of these fallacies violate, is the Rule of Fundamentality: a definition must name the characteristic that makes or explains the greatest number of the others.

Fallacies of inference

Ad hominem — attacking the arguer rather than the argument.
Non sequitur — a conclusion that does not follow from what preceded it.
Straw Man — refuting a position nobody holds in place of the one advanced.

How the two categories interact

Objectivism's claim is not that conceptual fallacies replace the traditional ones but that they usually come first. Most sustained disagreement in philosophy and politics is conducted in terms that were never reduced to their referents, which is why the arguments can run indefinitely without either side being reachable by evidence.

The corrective is the same in every case: reduction. Trace the disputed term down the hierarchy, level by level, to the concretes it ultimately rests on, and see whether anything is there. See Definitions, Context and Objectivity.

Discussion

References

Rand, Ayn. Introduction to Objectivist Epistemology. 2nd edition, Meridian, 1990.
Rand, Ayn. "Collectivized Ethics", The Virtue of Selfishness — the frozen abstraction.
Branden, Nathaniel. "The Stolen Concept", The Objectivist Newsletter, January 1963.
Peikoff, Leonard. Objectivism: The Philosophy of Ayn Rand, chapters 3 and 4.