I've been thinking about how SAN rolls work in Delta Green (and its predecessor, Call of Cthulhu). Sanity represents a character's connection to humanity - human culture, human beings, human science, and of course, human morality. It is determined by POW, which represents willpower. Sanity is lost through confrontation with forces that reveal how all these things are lies. Impossible entities and events, nauseating cruelty and violence, the realization of helplessness, and so on.
All this makes sense to me. The game mechanics line up with the abstract ideas they represent. Where things change is when we get into rolling for SAN.
The same statistic that determines security in the human narrative is used to diminish itself. Mechanically, the lower a character's SAN is, the faster they lose what little they have left. While there's a certain grim logic in that, I think it has a flaw, and have been thinking of an alternative approach.
In Lovecraft's work, it is not confidence in humanity that acts as a defense against the reality of the cosmos, but dumb ignorance. This is displayed many times, but I'll stick to using a single quote from Pickman's Model to showcase this:
"If there are any ghosts here, they’re the tame ghosts of a salt marsh and a shallow cove; and I want human ghosts—the ghosts of beings highly organised enough to have looked on hell and known the meaning of what they saw."
I think it's all well and good to roll SAN to resist helplessness and violence, but the Unnatural is a different story. It only really breaks people who were clever enough to know the meaning of what they saw or experienced.
The change I'm thinking of making here is rolling INT instead of SAN when faced with the Unnatural. Perhaps INT at +20%. A failed INT roll would equate to a successful SAN roll.
For example, If an Agent sees a ghoul and fails their INT roll they lose no SAN - it's just a freaky animal to them. An Agent who succeeds grasps that this creature was human once. They fully understand the implications of its terrible existence.
Does anyone have any feedback on this. Is it a change I should implement? Is my logic sound? Should I buff INT (maybe making higher INT lead to more skill improvements during the aftermath of an op, or making learning new skills easier during home scenes) to make up for the fact that having high INT is now liable to drive an Agent insane?
I like to look for real people/organizations/ideologies for inspiration. For example, I recently looked through a bunch of fascist esoterica as inspiration for making a Shub-Niggurath cult that patrols the US-Mexico border looking for migrants to kidnap and eat/sacrifice. Might is Right is pretty much a Shub-Niggurath cultist's bible.
I'm also basing the lead cultist of off Measurehead from Disco Elysium. His cranial measurements (which he tattooed on his head) are gradually changing as a result of mutagenic exposure to the Dark Mother and he's sinking even further into psychotic alt-right delusions to cope with it.