Lie by omission is more problematic concept than explicit lie. IMHO one has almost always moral duty to not explicitly lie, but just rarely duty to not 'lie' by

Lie by omission is more problematic concept than explicit lie. IMHO one has almost always moral duty to not explicitly lie, but just rarely duty to not 'lie' by omission, depends mainly on whether the person has duty to communicate that information or whether one actively tries to deceive.