ABSTRACT

Example 1.9. Let A and B be any standard sets. By transferring the sentences: “V x e T{A), My E x, y E A ” and “V/ E B A, / is a func­ tion with domain A and codomain 5 ”, it is proved that *Р(Л) C V(*A), and *(Æ^) C *2?*^ , respectively. Arguing similarly as in Example 1.7, one easily shows that these inclusions are equalities whenever both A and B are finite. In the infinite case, the inclusions are proper (cf. Proposition 1.25).