I AM fully conscious that the explanations on certain disputed points Of Catholic theology which I Offer to the public in the following pages are in many ways defective and incomplete. My immediate Object is to give a reply to a false accuser, and I feel that the sooner such reply is given the better. On the other hand the questions raised are of their own nature comprehensive in their bearin gs on human actions, and touch on principles that lie deep in the foundations of the moral order. I propose to myself, therefore, in the present undertaking to aim merely at a reply. I hope later to deal with the questions raised on their own merits; to show the perfect harmony that has from the beginning existed between natural reason and Divine revelation, and to make clear that theology has abided by the truth thus doubly verified, and has taught it openly and consistently, and with unswerving rectitude.