The Fifth Element

Different traditions give it different names: "The Mind" (wizards), "The Will" (warlocks), "The Heart" (witches), etc. It's the same in any case. The Fifth Element is Man himself (or Woman herself, or Elf itself, etc), most particularly the power of sentient willpower, of intelligence, of creativity, of hope, of all our best traits.

For powers, this skill deals with general, universal powers, such as dispelling, counterspelling, wards, etc. It is also the school for illusion, divination, and enchantment (except the really nasty stuff that belongs in The Dark Arts).

Those gifted in this school will find benefit to their innate magical defenses; this skill can be used to resist magical effects, even those not allowing a Will save.