I don't share that faith.
but a mind like ours can never perceive them independently, only in a rich subjective context.
Without rich subjective context, do they have meaning?
Symbols are nothing more than referents to patterns. I didn't think this definition was controversial at all, and the definition implies almost nothing, being strictly a definition. This is a common rigorous definition of "symbol".
Without rich subjective context, do they have meaning?
Of course not. A pattern is a pattern is a pattern. Without the subjective context, symbolic referents to "cat" and "dog" are essentially equivalent (technical caveat: assuming the patterns have the same Kolmogorov complexity). The corollary though, is that every interpretative context of a symbol will generally be unique. The contextual framework you put the symbol "cat" in is different from mine (since we don't share minds that I know of), so the contextual perception of that symbol will be different as well. The "cat" pattern exists objectively but we never perceive it that way; we only see it through the lens of how it interacts with the massive nest of interwoven patterns in our brains.