An intuitionistic version of Zermelo's proof that every choice set can be well-ordered (Q2758049)

The well-known theorem of Zermelo states that any set possessing a choice function for its set of non-empty subsets can be well-ordered. The paper under review presents a generalization of Zermelo's own proof of the theorem that is valid in any elementary topos. It is, however, doubtful that the proof may be called ``intuitionistic'', because the form of the generalized inductive definition it uses is not likely to be acceptable intuitionistically.