Just need a little clarification on the following line:
nec enim tuis es quem forma ista declarat, sed mens cuiusque is est quisque, non ea figura quae digito demonstrari potest.
for nor are you that form which declares itself to your friends, but each person is the mind of that form, not that shape which can be demonstrated by a finger
Or more idiomatically: for you are not the form which your friends see, but rather each person is the mind within that body, and not the shape which can be pointed to with a finger
I think the translation is generally correct, but there's one or two grammatical points I'm unsure of. What exactly does "quem" modify for example? Most likely, I think, it's Scipio Africanus, the addressee of the line, so it would be something like: for nor are you who declares himself to his friends that form....", but it doesn't sound correct.
Also, I'm treating "is" as in apposition with "quisque". Any comments on that?