The debate over gay marriage has heated up in the past few months as it has come to the foreground of domestic politics. Iowa, Vermont, and Maine have joined Connecticut and Massachusetts in legalizing same-sex marriage. Washington, D.C. legislators voted almost unanimously to recognize same-sex marriages performed in other states within the district. Meanwhile, the California Supreme Court upheld the result of its state’s voters’ decision to ban gay marriage. As gay marriage spreads throughout the union, both proponents of marriage equality and defenders of traditional marriage are fighting hard for their respective positions.

In my next two posts, I will examine three common arguments made by the traditional marriage side. While some readers may find this approach unbalanced, I focus on arguments made by this group of rhetors (a term for anyone who makes an argument) because their arguments generally arise from religious convictions concerning the institution of marriage–and the focus of this blog is the intersection of rhetoric and religion. I want to be clear that this post is not intended to demean the religious convictions of any believer. Rather, when believers enter the public sphere, they make arguments to support their convictions, and it is those arguments that are under examination here, not their personal beliefs.

The three common arguments I will examine in this two-part series are 1) the existence of two genders shows that same sex relationships are unnatural, 2) same-sex marriage advocates want to force their definition of marriage on everyone, and 3) because male-female copulation is necessary for the survival of the species, it is a fundamental and necessary aspect of the family unit. I have chosen excerpts from texts from three separate pro-traditional marriage sources–Focus on the Family, the National Organization for Marriage, and the American Family Association–to illustrate each of these arguments.

I will then analyze these excerpts using Aristotle’s foundational text on rhetoric, Rhetorica.  Specifically I will use Chapter 24 of Book II, in which Aristotle lists nine fallacious topics or arguments, what he calls “apparent enthymemes.” Enthymemes are the rhetorical equivalent of syllogisms, which are the basic unit of deduction in logic. While these fallacious arguments may be persuasive, but they remain logically invalid.

In particular, we will see three fallacious topics in this two-part series, and they correspond to the three common pro-traditional marriage arguments listed above: 1) argument from a non-necessary sign, 2) argument from exaggeration, and 3) argument from the omission of when and how. I will explain each fallacy as we go along.

For today’s post, I will focus on argument and fallacy number one, and will examine the last two arguments and fallacies in my next post.

#1 Two genders as a sign that same-sex relationships are unnatural: argument from a non-necessary sign

This first excerpt comes from the website of Focus on the Family, a highly visible conservative Christian group, most closely associated with James Dobson, which has taken a strong stand against same sex marriage. FOF argues that marriage is an institution sanctioned by God and can only be between a man and woman. One page on its website called “Marriage and Family” includes the following statements:

“The existence of two distinct genders reveals God’s design for sexuality, relationships and family. Both reflect the image of God, and both male and female are necessary for procreation and the optimal family structure for parenting children.”

The argument presented in these sentences could restated like this: That there are two genders needed for procreation demonstrates that God intended marriage, sexuality, and romantic relationships to be exclusively between men and women. The argument form could be written as such: the existence of X proves Y.

This is what Aristotle calls an argument from a non-necessary sign. Aristotle gives this example: “…Dionysius is a thief; for he is wicked. This is certainly nonsyllogistic: not every wicked man is a thief, but every thief is wicked.” In the example Aristotle provides, the rhetor argues backwards, starting from the point that Dionysius is wicked, concluding that he therefore is a thief. But as Aristotle points out, while all thieves are wicked, not all wicked people are thieves. A wicked person could be a murderer, a liar, or a tyrant. The rhetor in this example mistakenly takes Dionysius’ wickedness as a sign that he is a thief. While wickedness indicates that a person might be a thief, it could not be shown that this is necessarily so, and thus, wickedness is a non-necessary sign of being a thief. A rhetor cannot start from the premise of wickedness and conclude that a person is a thief without other evidence.

In the same way, in the argument made by FOF, while it may hold that everything God has intentionally designed exists, the reverse could hardly be proven to be true: everything that exists was intentionally designed by God. This would require one to believe that God designed cancer to ravage people’s bodies. Therefore, it cannot be argued that two genders are proof that sexual and romantic relationships must be exclusively heterosexual, anymore than cancer is proof that God intended for people to die painful and torturous deaths. Thus, we must conclude that the existence of two genders is a non-necessary sign of the parameters of marriage. This is a fallacious line of argument, and the logic is invalid.

While this is a fallacious line of argument, it is a common argument made by rhetors defending traditional marriage. Yet it’s only through open and honest dialogue with integrity, on all sides, that understanding can be had concerning this schismatic issue.

In my next post, we will explore two more common arguments made by the traditional marriage side and see why they too are argumentatively fallacious.