Whether there exist so-called 'absolutely undecidable' statements

Whether there exist so-called 'absolutely undecidable' statements, whose truth value can never be known or is ill-specified, is a controversial point in the philosophy of mathematics.

so-called 'absolutely undecidable' statements, whose truth value can never be known or is ill-specified,

Whether there exist so-called 'absolutely undecidable' statements, whose truth value can never be known or is ill-specified, is a controversial point in the philosophy of mathematics.

a single, maximal, universe of set theory

A central area of current philosophical debate in the foundations of mathematics concerns whether or not there is a single, maximal, universe of set theory.

an external mathematical reality

The traditional debate among philosophers of mathematics is whether there is an external mathematical reality, something out there to be discovered, or whether mathematics is the product of the human mind.