It is important to keep in mind that this was written for laypeople, not for working mathematicians. What is “concrete” for a working mathematician can be very abstract for an average reader. For example, thinking of a 5-dimensional space is very concrete for a mathematician but very abstract to other people.
It is important to keep in mind that this was written for laypeople, not for working mathematicians. What is “concrete” for a working mathematician can be very abstract for an average reader. For example, thinking of a 5-dimensional space is very concrete for a mathematician but very abstract to other people.