Independence results concerning Dedekindfinite sets

G. P. Monro
1975 Journal of the Australian Mathematical Society  
A Dedekind-finite set is one not equinumerous with any of its proper subsets; it is well known that the axiom of choice implies that all such sets are finite. In this paper we show that in the absence of the axiom of choice it is possible to construct Dedekind-finite sets which are large, in the sense that they can be mapped onto large ordinals; we extend the result to proper classes. It is also shown that the axiom of choice for countable sets is not implied by the assumption that all
more » ... n that all Dedekind-finite sets are finite.
doi:10.1017/s1446788700023521 fatcat:wsjipqn2wfg57lnlyitmpgkpbe