[FOM] Schroeder-Bernstein dual.

Bill Taylor W.Taylor at math.canterbury.ac.nz
Mon May 28 20:36:03 EDT 2007

Consider this "dual" to Shroeder-Bernstein:

**  If there are surjections   f: X --> Y
**                       and   g: Y --> X
**  then there is a bijection between X and Y.

It follows easily from AC, but seems to be strictly weaker.

Is there an easy model of ZF where this dual is false?

Does it have any interesting equivalents?


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