Abstract
According to the contralife argument, because both contraception and natural family planning entail at least a contralife motivation to have marital intercourse but avoid pregnancy, both should be forbidden—a conclusion rejected by the natural law tradition and Church teaching, which forbid contraception but permit NFP. This paper argues that the principle of double effect can be applied to explain why contraception is forbidden but NFP is permissible. This double-effect analysis evaluates the good effect of procreation and unity against the bad effect of lustful sexual pleasure. This paper argues that contraception fails to meet the conditions of the PDE, because it intends sexual pleasure in isolation from procreation and unity and is therefore forbidden. Conversely, NFP meets the conditions of the PDE because, as with all permissible sexual intercourse, it intends sexual pleasure in conjunction with procreation and unity and is therefore itself permissible.