Scio Occultus Res
Vulgar magic is magic that is obviously magic, and thus out of place and very obvious in the Mundane World. Using vulgar magic in the Mundane World can provoke Paradox, especially if witnessed by Sleepers, as it upsets the Quiescence that wraps them. For this reason, mages try to wrap their magic in coincidence and make it blend in to the consensus reality, using Covert Magic. Only in a Demesne is it safe for a mage to use vulgar magic in the Mundane World.