Dei Filius, On Faith and Reason, Canon 2

2. If any one shall say that human sciences are to be so freely treated that their assertions, although opposed to revealed doctrine, are to be held as true, and can not be condemned by the Church: let him be anathema.

Translation: Henry Edward Manning, Petri Privilegium (1871), reproduced in Philip Schaff, Creeds of Christendom II, via CCEL.