One of the defects of matrimonial consent is error. Error in canon law is a belief that is contrary to the legal reality, a false judgment concerning a thing, law, or an act in law. Error causes marriage to be invalid if it concerns a spouse or his or her attributes. Error as to the spouse affects will when it applies to his or her identity. Error in relation to the attributes affects will if it is directly and substantially intended. This error can affect any attribute as long as the latter is special and meaningful – only then does it become part of the object of consent and dominates the subject. The attribute becomes the main element of the object of matrimonial consent. Legal error – concerning unity, indissolubility, or sacramental dignity of marriage – renders marriage invalid since it determines will.