Mode of Expression
- Internal (heresy remains in heretic’s mind, no external sign)
- External (manifested by external signs, such as words, deeds, omissions, even if no one sees them).
How Many People Heard or Saw
- Occult (heresy manifested to no one, or to just a few).
- Public (heresy openly and externally manifested before many).
Merkelbach, Summa Theo. Moral. 1. 743