Mater et Magistra §199

¹⁹⁹ A provident God grants sufficient means to the human race to find a dignified solution to the problems attendant upon the transmission of human life. But these problems can become difficult of solution, or even insoluble, if man, led astray in mind and perverted in will, turns to such means as are opposed to right reason, and seeks ends that are contrary to his social nature and the intentions of Providence.