
p.2132
There’s always been a long running confusion among Homestuck readers about Aradia’s initial ghost form; along the lines of “what’s the difference between the spirits who wander Alternia and the ones who go into the domain of the Horrorterrors?” and the follow up “why wasn’t she in the dream bubbles like all the other dead people?”
The answer to the first question has always been obvious to me; there is no difference. Homestuck’s very structure is founded on patterns and repetition; if we can’t assume that anything that looks like a ghost and quacks like a ghost is therefore a ghost, how can we possibly begin to understand any of Homestuck? It’s the second question that really poses the obstacle, because on first reading the comic doesn’t really seem to bother with explaining this discrepancy.
But could it be that the answer to that question is actually… “Aradia was in the dream bubbles like all the other dead people”?
If we take the suggestion that a ghost, especially a ghost with psychic powers, can influence parts of the real world by influencing people’s memories of the real world at face value, then what is there, mechanically, to stop this from being the case for the entire time Aradia was dead? Why couldn’t our Aradia ghost simply have been living in a dream bubble memory of Alternia, using her psionic powers at long-distance in the same way we’ve seen psionics of her nature do before?
At first, it seems that something differentiating the two “different kinds” of ghosts is that those without psychic senses aren’t able to see the spirits that wander Alternia…

p.2190
…but given that just about anybody can sense ghosts in the dream bubbles - even Terezi, whose ability to sense people relies on their having some kind of “substance” to smell or taste - is it not just as easy to assume that Nepeta was unable to see Aradia on her screen because Aradia wasn’t actually there?
(This only stands out more when we take into account The Homestuck Epilogues, where ghosts are able to roam the real world and interact with the living just like they were regular people.)
Possibly the one “problem” that arises from this interpretation is how Aradia manages to prototype herself in a kernelsprite some thousands of voidyears away from her. But given that a kernel really only contains the “idea” of someone, is it such a stretch to imagine that the “memory” of something could also count, in the same way a ghost image counts as a solid object when used in alchemy? To put it in other words; if, as Andrew suggests, Aradia can literally transmit information at a (spooky) distance by whispering into the ear of a memory, does it not follow perfectly that Aradia could also digitally transmit information at a distance by placing herself in the memory of a kernelsprite?
There is even precedent in the comic for a ghost to be sucked into a kernel from the dream bubbles at a distance; because that’s exactly what happens in the creation of Jadesprite!
I think where this theory is the strongest isn’t just in the pure mechanics of it, though, but in how it plays into the story and the way Homestuck is told, as a series of questions followed by a series of answers. This whole “mystery” regarding the nature of ghosts becomes so much clearer when we recognise Aradia’s introduction as a ghost as the question - “there’s an afterlife in Homestuck? how does it work?” - and the introduction of the dream bubbles as the answer. Which is basically how Andrew phrases it in the commentary; Aradia whispering to her past self is a “cagey way of implying” something we didn’t already know and have been wondering about, i.e. where Aradia’s instructions have been coming from.
It has to be admitted, of course, that this conclusion is a little more obtuse and takes a little more digging than most of Homestuck’s question-answer revelations. It could easily be said, in fact, that this conclusion would be literally impossible to reach without the author’s commentary from nearly a decade later. But if Andrew’s print commentary has told us anything, it’s that Homestuck is full of details that the author fully intended to make clear in the text but was somehow just unable to before it became time to move on. For a prominent example; in what world has it “been implied that the mutual result of the red or black concupiscent ritual is the prodigious vomiting of genetic material”, as Andrew claims on p.312 of Book 4? “[…] to be perfectly honest, I can’t remember at all if this was implied anywhere in the text, or just in my imagination at some point over the last eight years.“