Hey there, recently I've been wanting to make a character who uses the Goetic Arts from the Infernal book. Particularly stuff like Commanding, which you can use to control demons. And other spirits of course but mostly demons, since it is the Ars Goetia after all.
Anyway, the Commanding description gives a list of common 'default' commands and their effects. The first of which is 'Advise Me', which compels 'any spirit to answer questions truthfully, though it may omit facts or mislead the sorcerer in other ways'.
Now, my mate tells me that this doesn't work on demons, since demons can never be compelled to tell the truth and that because the command just says it works on 'any spirit' instead of specifying demons, it can't supersede that general rule.
Personally, I think it'd be a bit weird to assume that the Ars Goetia do not in fact apply to demons. What would be the point?
It is not true that demons can never be compelled to tell the truth.
Hermetic magic can't force demons to tell the truth, or detect their lies.
But hermetic magic is not everything.
We know for sure that Divine Powers can compel a demon to answer a question truthfully (See "Adjuration" in RoP:D p48)
"Command" is an Infernal power, and while I can't find an explicit statement one way or the other, Infernal powers should also be able to force demons to speak the truth
On RoP:I, p.33, we read:
Hermetic magic cannot pierce any deception produced by a demon, although other varieties of Supernatural Powers (particularly Divine Powers) may well be able to do so.
More generally, the Limit of the Infernal, i.e. not being able to pierce a demon's deceptions, is one of the "Limits of Magic" (see ArM5, p.79-80), meaning that it affects almost all supernatural traditions drawing their power from Magic - but not from other Realms, and not necessarily all Magic ones either! In fact, many (most?) Magic traditions in the books break one Limit or another.
Not only do various other magical traditions break these limits, but Command is explicitly Infernal - not a magical power at all. There's no reason to expect it to conform to the "LImits of Magic".
Agree with previous posters; Infernal powers are not subject to the Limits of Magic. The supernatural effects of other Realms have their own separate (and less codified) limitations.
Now, one point that's made about Infernal powers is they'll usually do what you want or give you true information, but distorted or controlled subtly to push you towards further evil. So "you can compel them to answer truthfully" may not let you filter out duplicitous intent, where the demon frames true statements in ways that encourage drawing the wrong conclusions, or taking the wrong actions. But the statements do still have to be true independently, which they wouldn't have to be if you were using a Hermetic lie detection spell.
Thanks for the help, everyone! Unfortunately they're really insistent on this not working, even after I linked these posts, so I will not be playing the goetic character. It's a shame but what can you do?
Sorry to hear. Some people are just too Hermetic-brained.