A phrase by phrase analysis of the final sentence of paragraph 10, Chapter 2: “Philosophical Detection” from “Philosophy Who Needs It?” by Ayn Randi.
The story so far: Rand has been trying to refute David Hume, based on the following straw man: ‘Don’t be so sure- nobody can be certain of anything.’ ‘Don’t be so sure’ refers to the choice of psychological uncertainty and ‘nobody can be certain of anything’ refers to the absolute uncertainty of inductive logic, per Hume.
Final sentence: “Furthermore, if one tried to accept that catch phrase, one would find that its second part contradicts its first: if nobody can be certain of anything, then everybody can be certain of everything he pleases- since it cannot be refuted, and he can claim he is not certain he is certain (which is the purpose of that notion)ii.”
Phrase by phrase analysis:
“its second part contradicts its first:”
- Rand asserts the general premise “nobody can be certain” regarding logical uncertainty is contradictory to the personal imperative “don’t be so sure” regarding psychological uncertainty, but no evidence will be presented. The rest of her sentence following the colon is a different topic.
“if nobody can be certain of anything, then everybody can be certain of everything he pleases”
- Rand’s assertion is irrational and grammatically flawed. “If nobody can be certain of anything, then everybody can be certain of nothing” would be correct.
“certain of everything he pleases”
- “Certain of everything he pleases” refers to the object of certainty, “Don’t be so sure” refers to the subjective attitude, while “nobody can be certain” refers to whether certainty itself is logically possible. Rand is confusing apples, oranges and grapefruit.
- This does not explain how “nobody can be certain” could contradict “ don’t be so sure”. Rand merely replaces “don’t be so sure” with “certain of everything he pleases” even though the new phrase is about a completely different thing.
“- since it cannot be refuted,”
- Rand asserts lack of certainty means “everything” cannot be refuted. Since Hume’s inductive uncertainty allows for refutation within deductive logic, Rand’s statement is false.
- Since the modern scientific method of refutation through falsification is allowed by Hume’s inductive uncertainty, Rand’s statement is false.
- Rand is not explaining how “don’t be so sure” could be contradicted by “nobody can be certain”. Instead, she is trying to justify her new phrase, off on a tangent.
“and he can claim he is not certain he is certain”.
- Rand asserts people can claim to be uncertain of their certainty as proof they are certain. That is illogical. There is no explanation of how that would succeed or be expected to.
- By using “claim”, an imputation of dishonesty is leveled.
- Still nothing related to how the uncertainty of inductive logic could contradict emotional uncertainty.
“(which is the purpose of that notion).”
- Her parenthetical aside accuses everybody “claiming” uncertainty of creating her straw man for the deliberate “purpose” of pretending to not be certain of uncertain things everybody is arbitrarily deciding to be certain of.
- Rand gives a possible motive for this complicated conspiracy later in the chapter: “No one can be certain of anything” is a “rationalization of a feeling of envy and hatred toward those who are certain”iii; but she provides no evidence that David Hume was envious or hated people who were certain, and she makes no mention of Hume’s deductive logic.
- Her sentence and paragraph ends without solving the mystery of how “nobody is certain” contradicts “don’t be so sure”.
Rand’s sentence isn’t rational or logical or grammatical. It’s a plate of spaghetti.
iSignet edition, Penguin Books, 1984