Hi Bk:
Although answer choice E does NOT parallel the structure of the stem, and therefore is not the credited response, you are correct that it is a valid set of statements.
However, I think your diagramming for the second statement is a little off.
You wrote:
GP
A
Not A
I
Therefore, GP
Not I
The statement "No artists are intellectuals" is better diagrammed as
A
I
because it is the state of being an artist that is sufficient to tell us that the individual is not an intellectual. We can see that this is the valid way to diagram it by testing the contrapositive:
I
A
Meaning that if we know someone is an intellectual, that is sufficient to tell us that the person is not an artist.
If we did the contrapositive of your version, we'd have
I A, meaning not being an intellectual is sufficient to tell us that you are an artist. This moves us beyond the original statement that "no artists are intellectuals."
The second part of your question, regarding LSAT's use of the term "some": anytime something is true for ALL of the items in a group, it is also true for SOME members of the group. "Some," on the LSAT, includes the case of "all."
I hope that is helpful!
