The Morris model

Douglass B. Morris announced in 1970 that it is consistent with $\mathsf {ZF}$ that ``For every $\alpha$, there exists a set $A_\alpha$ which is the countable union of countable sets, and $\mathcal P(A_\alpha )$ can be partitioned into $\aleph _\alpha$ non-empty sets''. The result was never published in a journal (it was proved in full in Morris' dissertation) and seems to have been lost, save a mention in Jech's ``Axiom of Choice''. We provide a proof using modern tools derived from recent work of the author. We also prove a new preservation theorem for general products of symmetric systems, which we use to obtain the consistency of Dependent Choice with the above statement (replacing ``countable union of countable sets'' by ``union of $\kappa$ sets of size $\kappa$'').