On Well Founded sets and the Axiom of Choice
Prove that, if we admit the axiom of functional choice
(look at library Logic.ClassicalChoice),
then if some relation R is not well founded, there exists a
strictly decreasing (w.r.t. R) infinite sequence.
Remarks
Look also at that exercise
The Axiom of Functional Choice is presented on Coq's FAQ
(in Coq's documentation ).
Look at the section "The Logic of Coq : Axioms".
Solution
Look at this file .