Dear Eric.
I've read you article. It's interesting. I think it's probably because I come from a different understanding of these things that I'm sometimes struggling to understand your meaning. By this I mean it's not because you aren't expressing yourself clearly, rather that we see the world through different eyes.
A couple of points:
I admit that I haven't read Epictetus, Marcus Aurelius, and Seneca, although I have a vague idea of what they're talking about. The language and concepts you're using are much more 20th century and later. So it's not clear how all this relates to Stoicism, although that is the point you're trying to make.
Sometimes your point is clear, e.g. Conditioning, but sometimes less clear, e.g. Symbol. I'm a big fan of Carl Jung, who says: “A word or an image is symbolic when it implies something more than its obvious and immediate meaning. It has a wider 'unconscious' aspect that is never precisely defined or fully explained. Nor can one hope to define it or explain it. As the mind explores the symbol, it is led to ideas that lie beyond the grasp of reason... Because there are innumerable things beyond the range of human understanding, we constantly use symbolic terms to represent concepts that we cannot define or fully comprehend” [Man and His Symbols].
You say that if my “footlight of consciousness” notices a table, for example, then that is a symbol. So it's not clear to me what you mean. In what sense is the table a symbol? Are we entering the realm of Platonic ideas here?
Best wishes.