Have any modern thinkers gone further into the concept of archetypes?
It seems to me that Jung investigated the relationship between the archetype and the individual/society; but didn’t do as much investigating of the archetypes themselves.
Anyone have a reference/opinion?
There is no such thing as an “archetype in itself”; investigating an archetype always means investigating the relationship between it and men.
An archetype is a symbol. Now let us suppose we encounter the word “lion” in an occult text. The word “lion” is a symbol that refers to a certain beast of prey. But that beast of prey is not meant here. Sure, the word “lion” is meant to invoke that beast of prey, but that beast of prey here is a symbol itself. But this beast of prey is not a symbol of itself; it has a symbolic meaning attached to it, by humans. Likewise, a visual image of such a beast may be more than a depiction: it may be a symbol of something else, something inexpressible.