Bertrand Russell talked about the “unsolved“ philosophical problem of mathematical reality
Mathematics is the byproduct of the orderly mind of the Creator God.
Bertrand could not (would not) see this very simple, profound truth. Since he was intelligent he just decided to reject the truth.
There is no unsolved mystery of mathematical reality.
It is only the blind who cannot see the Truth. That blindness is of the heart and has nothing to do with intellect or education.
The fool has said in his heart, "There is no God" .
Mathematics (order) is proof of the Creator. Man simply discovered mathematics while investigating the order in the universe.