In “The Great Math War,” Jason Socrates Bardi takes on a battle for the soul of numbers that divided the experts of its day.

In mid-October, Justin Gilmer flew from California to New York to attend a friend’s wedding. While on the East Coast he visited his former adviser, Michael Saks, a mathematician at Rutgers University, ...

Students in Melissa Williams' kindergarten class at the Westminster School in Atlanta, Georgia, practice connecting quantities to written numbers — a key part of number sense. Credit: Holly Korbey for ...