I think it is called sentence subject. Sorry if I am wrong.
The sentence For thousand of years, we have been making maps to represent the physical world has a pronoun in the nominative case. the pronoun is WE. It is the only pronoun which is the subject of a verb
Correction:
-Reading fiction helps students learn how to empathize
Or…
-Students reading fiction will improve how to be empathic
If you choose the 2nd one give an example how they learned to be empathic, before the book then after :).
