Is Marriage Just About Procreation?
Where can Catholics find the reasoned proof and answer from nature that the primary purpose of the marriage act is procreation?
Nature determines that each species of the animal kingdom generates offspring. The offspring in turn generates more offspring. In this way, the species is preserved. Human nature is the same. You do not need marriage to have babies, because human sexual activity naturally generates offspring whether the couple are married or not.
Marriage as a cultural and legal institution appears to have grown from the social necessity to formalise the marital union so that the couple can live in a structured and socially acceptable relationship to protect and bring up their children, and so contribute to the growth and preservation of the community.
It is an essential element of marriage that the couple have the exclusive right to each other’s bodies. As in the animal kingdom, producing offspring is the normal and natural outcome of human sexual intercourse. But, as you ask, is having children the primary reason why a married couple have sex?
Today, many would answer no. Sex within marriage is frequently regarded as a matter of strengthening the bonds of love, security and mutual pleasure. Frequently, also, couples use means artificial and natural to exclude the possibility of having children. And, as you can have children without marriage, so you can have marriage without children, especially in cases of infertility or being of an age beyond procreating.
The Church accepts that it is the natural outcome of the marriage act that babies can be born. But it sees this as God’s plan, and therefore it cannot make any argument about the purpose of the marriage act without reference to the divine will. This is perhaps most clearly expressed in Genesis. God made male and female in his own image and told them to be fruitful, multiply and fill the earth. See also Ephesians 5.
Canon law tells us that marriage is a sacrament of its own very nature ordered to the well-being of the spouses and the procreation and upbringing of children (c1055). This is based on centuries of tradition and doctrine combined with human biology and social evolution, and would include the teaching that contraception is unacceptable because it thwarts the divine will.
The Church, you see, does not claim to find motives from nature that the primary purpose of the marriage act is procreation.