written in stone

written in stone

Permanently fixed or firmly established; incapable of being changed. Often used in the negative. The deal isn't yet written in stone, but we're confident it will go ahead as hoped.

See also: stone, written

in stone, cast/carved/written

Completely set, unchangeable. This phrase is often put in the negative—something is not cast in stone. It alludes to sculpture, where to cast means to pour and harden a material into a final form, and possibly also to the epitaphs engraved on gravestones. The first usage dates from the early 1500s. Most often it appears in such statements as, “Of course we can change it; this proposal is not cast in stone.”

See also: carve, cast, written