Sacrifice

Sacrifice, in Objectivism, is the surrender of a greater value for the sake of a lesser one or of a non-value. The definition is deliberately narrow: it is what distinguishes the concept from ordinary trade-offs, investment and generosity, all of which involve giving something up and none of which Objectivism condemns.

“Sacrifice is the surrender of a greater value for the sake of a lesser one or of a non-value.”
~ Ayn Rand, Atlas Shrugged

The test is the direction of the exchange

Every action forgoes something. Spending money forgoes what else it could have bought; spending an evening with a friend forgoes the work not done. If "sacrifice" named that, it would name all human action and mean nothing.

What the concept isolates is the case where the exchange runs against one's own hierarchy of values:

Paying for something one wants more is not a sacrifice. Tuition for a degree one wants, hours for a project one cares about, money for a gift to someone one loves — in each case the thing gained ranks higher than the thing given up.
Risking one's life for a person one loves is not a sacrifice. Rand's argument, made in "The Ethics of Emergencies", is that a man who would not want to live without a particular value is not trading down when he defends it. He is acting on his own hierarchy, at the top of it.
Giving to a stranger from surplus is not a sacrifice. Benevolence toward people one has no reason to think ill of costs little and reflects a general estimate of human beings as potential values. What Objectivism denies is that need creates an obligation.
What is a sacrifice is giving up a career for the approval of people one does not respect, or a conviction for the sake of peace at a dinner table, or a child's future for a cause one has not examined. The mark is that the greater value goes to the lesser.

Why altruism requires it

The Objectivist objection to altruism is not that it recommends kindness but that it makes sacrifice the standard of moral worth. Once the measure of virtue is what an act costs the actor rather than what it achieves, several things follow:

An action ceases to be moral to the extent that one wants to do it, which puts morality permanently at odds with a person's own life.
The beneficiary's need, rather than his merit, becomes the claim, which sets aside justice entirely.
Because no one can practise it consistently and live, the code is honoured mainly in guilt — which Rand argued is its actual social function.

See Egoism and Trader Principle for the relation Objectivism puts in its place.

Common misunderstandings

That Objectivism forbids helping anyone. It denies that need is a mortgage on one's life. Helping people and causes one values is ordinary and expected.
That any loss counts. A loss inflicted by circumstance is a misfortune, not a sacrifice. The concept applies to a choice.
That soldiers, parents and rescuers are therefore condemned. Objectivism holds the opposite. Acting to protect what one values most, at great cost and risk, is the clearest case of acting on one's own values rather than against them.
That "sacrifice" is just a word for compromise. Compromise between people who share a principle is trade. Sacrifice is the surrender of the principle itself; see Integrity.

Discussion

References

Rand, Ayn. "The Ethics of Emergencies", The Virtue of Selfishness. New American Library, 1964.
Rand, Ayn. "The Objectivist Ethics", The Virtue of Selfishness.
Rand, Ayn. Atlas Shrugged — Galt's speech, on sacrifice and the code of death.
Peikoff, Leonard. Objectivism: The Philosophy of Ayn Rand, chapter 8.

External links

Sacrifice at the Ayn Rand Lexicon