Summary
Highlights
Justice is not only about individual relations but also applies to the duties of the state to its citizens (distributive justice), citizens' duties to the state (legal justice), and individuals' duties to each other (commutative justice).
It is wrong to harm others' bodies, reputations, or property. Murder is a grave wrong because it goes against love and justice, disrupts social order, contradicts human nature as a social being, and usurps God's dominion over life and death, violating human dignity and moral law.
Self-defense is morally justified under certain conditions, such as imminent danger to life or serious bodily harm, no other means of escape, and using only necessary force to repel aggression.
Honor and a good name are invaluable assets. Deliberate acts that damage another's reputation, such as lying or slander, are serious moral violations that erode trust and societal harmony.
Truthfulness is a moral duty. Lying is wrong because it goes against the natural purpose of speech, which is communication, and it disturbs social order by undermining mutual trust, a cornerstone of peace and harmony.
Sexuality has biological and psychological/personal levels. Biologically, its purpose is reproduction and species continuation. Psychologically, it expresses love, self-giving, and unity between spouses.
Contraception is considered wrong because it contradicts the true meaning of sexual union, which is meant to express love, self-giving, and openness to procreation. It aims to prevent reproduction.
The rhythm method is allowed if there is no contraceptive intention and if it maintains the meaning of sex and openness to life. Contraceptive pills are allowed as medicine to regulate menstrual cycles but not for birth control or to prevent ovulation.
Sex, from scientific and spiritual viewpoints, is for reproduction, love, and self-giving. Contraception is considered wrong because it contradicts these core meanings and purposes of sexual union.
The Humanae Vitae states that abortion and direct sterilization are always wrong. Pope John Paul II emphasizes that life is sacred from conception, and violating it goes against God's gift and harms society. Protecting life upholds the moral order.