Dear Harvey,

- People seem to be blackboxing the idea of “good mathematics” or “good set theory.” These notions are desperately in need of some sort of elucidation particularly by people with foundational sensibilities.

In a recent workshop, some mathematicians, historians, and philosophers undertook a preliminary, collaborative exploration of the notion of ‘mathematical depth’.

A special issue of *Philosophia Mathematica* is in the works.

With all best wishes,

Pen