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All terms
Tier 4 · The Fiduciary Core

Legal tender

Money a creditor must accept in settlement of a debt by law — one of the props, alongside tax liabilities, that makes an intrinsically worthless token universally acceptable.

Also called: fiat currency, chartalism, fiduciary currency.

Legal tender law is narrower than people assume. It governs the settlement of debts already incurred; it does not oblige a shop to accept cash for a sandwich, and most countries let sellers set their own terms in advance.

The stronger prop is taxation. A government that demands payment in a particular unit creates continuous, non-optional demand for it — the chartalist argument that taxes drive money, and the reason a currency's acceptability tracks the reach of the state that issues it.

The rest is institutional confidence: an independent central bank, enforceable contracts, and a plausible expectation that the unit will still mean something next year. None of these is a physical backing, which is exactly why the arrangement is called fiduciary.

The mechanics

Legal prop
Statute makes the unit valid for settling debts within the jurisdiction.
Fiscal prop
Tax liabilities denominated in the unit create standing demand for it.
Institutional prop
Credibility of the issuer, and the expectation that it will be defended.

The common misreading

That fiat money is 'backed by nothing'. It is backed by an enforceable claim structure — tax obligations, courts, and a central bank — which is a different thing from being backed by a commodity.

Primary sources

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