Is-Ought Dichotomy

The is-ought dichotomy is the claim that no statement about what ought to be done can be derived from statements about what is — that facts and values belong to separate realms with no bridge between them. Objectivism rejects it, holding that the concept of value has no meaning apart from the facts of life, and that the gap appears only when ethics is detached from its biological base.

“It is only the concept of "Life" that makes the concept of "Value" possible.”
~ Ayn Rand, "The Objectivist Ethics", The Virtue of Selfishness

The problem as it is usually posed

The dichotomy is normally credited to David Hume, who observed that writers on morality slide without notice from propositions joined by "is" to propositions joined by "ought", and that the move is never explained. Later philosophers hardened the observation into a rule: no set of descriptive premises entails an evaluative conclusion.

The consequence, if the rule holds, is that ethics has no cognitive standing. Values become expressions of preference, emotion or social convention, and disputes about them cannot be settled by evidence. Objectivism takes that consequence seriously — it is the reason ethics collapsed into subjectivism — and attacks the premise rather than trying to live with the result.

The Objectivist answer

Rand's argument does not attempt to squeeze an "ought" out of arbitrary facts. It asks a prior question that the dichotomy skips: what are values, and what kind of entity has them?

Value presupposes an alternative. To value is to act to gain or keep something. That is only intelligible where something is at stake, where an outcome can go one way or another. In a universe of indestructible matter there would be nothing for anything to be for or against.
Only living things face a fundamental alternative. An organism is a self-sustaining, self-generated entity whose continued existence depends on a specific course of action. It can go out of existence, and inanimate matter cannot. Existence or non-existence is the alternative that gives rise to the whole category of goal-directed action.
Therefore life is the standard that makes values possible. A thing is good or bad for an organism, measured against the requirements of its survival. This is not a value read into nature; it is an observation of what living entities in fact do, and of what the concept of value has always been about.
For man, the standard is his own life qua man. Man has no automatic code of survival. He does not know automatically what is food, what is a threat, or how to produce anything, and his means of finding out is reason. Ethics is the identification of the principles a being of that kind needs in order to live. See Ethics, Rationality and Virtues.

So the "ought" is not smuggled in. Given that an entity is alive and that its life depends on a specific course of action, facts about that entity's nature already are facts about what it must do. "This is poison" and "you ought not drink it" are not two claims from separate realms; the second is what the first means for a being who intends to go on existing.

The role of the choice to live

Objectivism holds that morality is not a categorical imperative hanging in the air. The "ought" is conditional on the choice to live, which is part of why Rand called her ethics objective rather than intrinsic: it tells a man what to do given that he has chosen to remain in existence, and it has nothing to say to someone who has genuinely abandoned that choice.

Critics treat this as reintroducing the gap one level down — if the basic choice is arbitrary, so is everything resting on it. The Objectivist reply is that the choice to live is not itself a moral choice but the precondition of morality, since evaluation exists only inside it, and that the alternative is not a competing set of values but the absence of the concept.

This is the most disputed point in the literature. Whether the choice to live is pre-moral, whether anything validates it, and how Rand's own remarks on it fit together are argued over among writers sympathetic to Objectivism and not only by opponents. Treat the summary above as the standard presentation and the surrounding argument as unsettled rather than closed.

Related dichotomies

Objectivism regards this split as one of a family produced by the same underlying error of detaching concepts from the perceptual reality they were formed to organise:

The analytic-synthetic dichotomy, separating truths of meaning from truths of fact.
The reason-emotion dichotomy, separating the faculty that identifies from the faculty that responds.
The theory-practice dichotomy, separating what is true from what works.
The mind-body dichotomy, of which Rand treated the rest as consequences.

Common misunderstandings

That Objectivism claims values are found in nature the way rocks are. It does not. Values are relational: something is a value to an entity and for a purpose. Rejecting the dichotomy is not a return to intrinsicism. See Objectivity.
That "survival" means bare physical continuation. The standard is man's life qua man — life proper to a rational being across a full lifespan, not the momentary avoidance of death. A course of action that keeps someone breathing while destroying the means by which he lives does not meet it.
That it makes ethics a matter of calculating consequences case by case. Objectivism is an ethics of principles, on the grounds that a being who plans long-range cannot re-derive his conduct from scratch at every moment. See Principle.
That the answer is merely a definition. The claim is that the ordinary concept of value already carries this structure, and that identifying it is a discovery about what people have always meant by the word.

Discussion

References

Rand, Ayn. "The Objectivist Ethics", The Virtue of Selfishness. New American Library, 1964.
Rand, Ayn. Introduction to Objectivist Epistemology, chapter 6. The Objectivist, 1967.
Peikoff, Leonard. Objectivism: The Philosophy of Ayn Rand, chapter 7.

External links

Is-Ought Dichotomy at the Ayn Rand Lexicon