A Reminder from The Catholic Encyclopedia
Degrees of heresy
Both matter and form of heresy admit of degrees which find expression in the following technical formula of theology and canon law. Pertinacious adhesion to a doctrine contradictory to a point of faith clearly defined by the Church is heresy pure and simple,heresy in the first degree. But if the doctrine in question has not been expressly "defined" or is not clearly proposed as an article of faith in the ordinary, authorized teaching of the Church, an opinion opposed to it is styled sententia haeresi proxima, that is, an opinion approaching heresy. Next, a doctrinal proposition, without directly contradicting a received dogma, may yet involvelogical consequences at variance with revealed truth. Such a proposition is not heretical, it is a propositio theologice erronea, that is, erroneous in theology. Further, the opposition to an article of faith may not be strictly demonstrable, but only reach a certain degree of probability. In that case the doctrine is termed sententia de haeresi suspecta, haeresim sapiens; that is, an opinion suspected, or savouring, of heresy (see THEOLOGICAL CENSURES).