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Independence results concerning Dedekindfinite sets

Published online by Cambridge University Press:  09 April 2009

G. P. Monro
G. P. Monro
Affiliation:
Department of Pure Mathematics, University of Sydney, Sydney, 2006, Australia
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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 Dedekind-finite sets are finite.

Information

Type
Research Article
Information
Journal of the Australian Mathematical Society , Volume 19 , Issue 1 , February 1975 , pp. 35 - 46
Copyright
Copyright © Australian Mathematical Society 1975

References

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