Those terms are not unique. Ka is an Egyptian word whose meaning has varied across time (depending on context it can mean "soul" or "guardian angel"), and Simulacrum is a word referring to any artificially constructed object. Even the names of the summoned creatures are taken directly from The Magician's Companion, a common resource for occultists.
Every term in the game either comes from playing with the English, Latin, and Hebrew dictionaries or from well-known occult terminology. Even the phrase "occult science" predates the game by nearly a century. When it says "occult roleplaying" on