Epistemologically speaking, why are subjects which deal with “small concepts”, the most difficult to learn?
There are in reality no “large” or “small” concepts. They just deal with, denote, or refer to entities which are on a continuum from macro to micro. As to which is more difficult to understand or deal with, I think it depends on the individual. Some are much happier dealing with Chemistry than Biology, and some prefer Grammar to Literature. This is largely a measure of how happy people are in dealing with levels of abstraction. Whereas Biology is at some levels relatively empirical, with various bits of a body being demonstrably anatomically related to others, Chemistry deals much more in abstracted concepts such as forces and atomic bonding, etc. This degree of abstraction is also found at the most macro levels: the same mental skills are probably needed in dealing with big things in Cosmology, Metaphysics, and Ontology.
