Board Thread:General Discussion/@comment-28262674-20160606011530/@comment-27701762-20160611202302

ITSPATRICKYALLS wrote: This theory is debunkable, but it's just a theory. Plus, I think Toby made this intentional. I never said Toby put these things in unintentionally. What I said is that his intention was for these things to be references, not indications that Sans and Papyrus come from the Earthbound universe. The fact that Toby made these references intentionally is fully compatible with the claim that they are just references. In fact, in order for them to be references they would need to be intentional.

Saying "it's just a theory" doesn't mean anything, though. A theory is meant to be an explanation of the game's world by way of the "truth," which we understand to be the intention of the game's creator. If a theory is debunked, then it is false. A theory which is false should be abandoned. A theory does not have any special status for belief simply by virtue of the fact that it is a theory.

If, however, you would like to continue believing that Papyrus is a Starman and Sans is Ness, then you and everyone else are perfectly free to adopt it as headcanon. You may hold whatever beliefs you would like about the nature of the world, even in spite of evidence to the contrary, even if you yourself are willing to acknowledge that the belief isn't true by the definition given above. It just means that it isn't a theory. In turn, headcanon doesn't have to be held to the same standards as a theory. But if you want to put the idea forward as a theory, then its falsifiability comes back into play.