Rules of mathematics are constructed and arbitrary in much the same way soccer rules are, but from any given set of rules specific conclusions follow objectively. It doesn’t make much sense to say that a given set of axioms and derivation rules is “objectively true”(*), but it does make sense to say that the theorems “objectively follow” from the axioms and derivation rules.
So mathematics is not really of much help to any concept of objective morality.
(*) I am aware that there are mathematicians who believe in “objectively true” systems of mathematics. They’re deluding themselves by confusing other qualities such as power, elegance, usefulness, or beauty for objective truth.
Rules of mathematics are constructed and arbitrary in much the same way soccer rules are, but from any given set of rules specific conclusions follow objectively. It doesn’t make much sense to say that a given set of axioms and derivation rules is “objectively true”(*), but it does make sense to say that the theorems “objectively follow” from the axioms and derivation rules.
So mathematics is not really of much help to any concept of objective morality.
(*) I am aware that there are mathematicians who believe in “objectively true” systems of mathematics. They’re deluding themselves by confusing other qualities such as power, elegance, usefulness, or beauty for objective truth.