Indirect self-reference describes an object referring to itself indirectly.

For example, define the function f such that f(x) = "x(x)". Then, the object f(f) = "f(f)". This object could be seen as indirectly referring to itself.

give more, better examples...

It is an important concept in mathematics and logic. Indirect self-reference was studied in great depth by W. V. Quine, and occupies a central place in the proof of Gödel's incompleteness theorem.

See also: