Rand's Razor

Rand's Razor is Ayn Rand's rule for disciplining the formation and use of concepts: name your primaries. Stated at greater length, it holds that concepts are not to be multiplied beyond necessity, and — the half that distinguishes it from older razors — that they are not to be integrated in disregard of necessity either.

“Concepts are not to be multiplied beyond necessity—the corollary of which is: nor are they to be integrated in disregard of necessity.”
   ~ Ayn Rand, Introduction to Objectivist Epistemology

The two formulations

Rand stated the rule in two places and two forms, and they are the same rule seen from different ends.

In Introduction to Objectivist Epistemology it appears as a principle of concept-formation: a new concept is justified when it isolates a group of existents whose distinguishing characteristic makes a difference that the existing concepts cannot capture, and it is not justified merely because a distinction can be drawn. The corollary matters equally — refusing to form a concept that reality requires is as much a failure as inventing one it does not.

In "Philosophical Detection", in Philosophy: Who Needs It, it appears as an instruction to the reader: name your primaries. Identify what you are treating as irreducible, as the starting point from which the rest of your reasoning proceeds, and say so out loud. The two are connected because an unnamed primary is precisely a concept that has escaped the check the first formulation imposes.

Why "name your primaries"

The rule is aimed at a specific failure. Arguments frequently rest on something the arguer has never stated — a term he treats as needing no explanation, an assumption doing the real work. Because it is unnamed, it cannot be examined, and because it cannot be examined, the argument cannot be evaluated at all.

Naming the primary forces two questions into the open. Is this thing genuinely irreducible, or does it rest on something more basic that is being skipped? And if it is being treated as a starting point, what validates it? A great deal of philosophical dispute, on Rand's analysis, is conducted between positions whose real disagreement is at a level neither party has stated.

The rule therefore functions as a companion to several other Objectivist tools: the demand that a concept be tied back to perceptual reality (see Floating Abstraction), the demand that a definition name a fundamental characteristic rather than any true one (see Rule of Fundamentality and Fundamental), and the identification of arguments that presuppose what they deny (see Fallacy of the stolen concept).

Compared with Occam's Razor

The traditional razor attributed to William of Ockham concerns entities: do not posit more of them than the explanation requires. Rand's concerns concepts, which is a different subject, and the difference produces two divergences.

• It is symmetrical. Occam's razor cuts in one direction, against multiplication. Rand's cuts both ways, because a mind that fails to form a needed concept has lost cognitive ground just as surely as one that invents an unneeded one. The corollary is the part that is genuinely hers.
• The standard is cognitive need, not simplicity. What licenses a concept is not that it makes the account tidier but that it is required to organise the facts economically — that without it a range of existents could not be held and used by a mind of limited capacity. See Unit-economy and Crow-epistemology.

Objectivism does not treat simplicity as a criterion of truth. The economy in question is economy of the means of holding knowledge, dictated by the limits of human consciousness, not a claim that reality prefers to be simple.

In practice

• Against a coined term doing unexplained work in an argument: ask what existents it isolates and what distinguishes them from the nearest existing concept.
• Against a package-deal: ask whether the things being carried under one word actually share the essential characteristic the word claims for them.
• Against a stalled dispute: ask each side to name the primary. Frequently one of them has been treating a conclusion as a starting point.
• Against one's own reasoning: identify where the chain of justification is being terminated, and check whether it was terminated at an axiom or merely at the point where introspection stopped. See Axioms and Proof.

See also

• Concept · Concept formation · Definitions · Fundamental
• Rule of Fundamentality · Unit-economy · Crow-epistemology · Measurement omission
• Floating Abstraction · Frozen Abstraction · Package-Deal · Invalid Concept
• Fallacy of the stolen concept · Logic · Objectivity · Principle

Discussion

• Attribute vs quality
• Objectivist epistemology and metaphysics
• A definitive criticism of Objectivist epistemology

References

• Rand, Ayn. Introduction to Objectivist Epistemology, chapter 7. The Objectivist, 1967.
• Rand, Ayn. "Philosophical Detection", Philosophy: Who Needs It. Bobbs-Merrill, 1982.
• Peikoff, Leonard. Objectivism: The Philosophy of Ayn Rand, chapter 3.

External links

• Rand's Razor at the Ayn Rand Lexicon