From the introduction:
I have always had a problem with the way that the various Ravenloft rulebooks have handled fear, horror and madness checks, but madness in particular. In real life and in most Gothic literature, madness is a gradual thing, usually built up over long periods of time; think of the madness as described in Poe or even Lovecraft. The Madness checks from Ravenloft and later Masque of the Red Death were an all or nothing affair, one failed roll could turn anyone into a raving lunatic. Plus the rules in The Realms of Terror and the Masque of the Red Death books mostly dealt with madness as an after effect of psionic interference. Of course millions of people suffer from mental illness without the “benefit” of being psionic.
It occurred to me then that sanity was a human attribute, much like intelligence, and it should be treated as such. Both the Dungeon Master’s Guide and The Players Handbook make many references to insanity but very few rules or guidelines for play. I will attempt to fix that.