Stephen J. Heaney is Associate Professor of Philosophy at the
University of Saint Thomas in Saint Paul, MN. This article has been reproduced with permission from Public Discourse

Abraham Lincoln once asked how many legs a dog
has if we call a tail a leg. The answer, he said, is four: calling a
tail a leg does not make it so. We chuckle and move on.

But what if people began to argue that a tail really is a leg? They
might say that what defines the leg is that it is an appendage of the
dog’s body, that it contains bone and muscle covered with skin and
fur—just like a tail. Tails just happen to come out of the body at a
different angle than other legs. When a tail hangs down low, who can
tell the difference?

This is an example of defining a thing according to non-essential
characteristics. It is like saying that a soldier is “a man who wears a
uniform and carries a gun,” or calling a football stadium “a field
surrounded by lots of seats.” It may be true in each case, but fails to
tell the story.

To continue the figure, the bones and muscle of a leg are different
from the tail. They have to support the dog and make it possible to run
and jump. No matter how well the dog can wag its tail, it will not
propel it anywhere. The issue, then, is not that the leg has bones and
muscles, but how they are put together, and why. A
tail is not a leg, because it is impossible for it to function as one.

Some may respond that there are legs on many dogs that cannot propel
the dog anywhere. They have broken bones, or withered muscle, or have
lost the foot in an accident. If not all legs can propel the animal
forward, then this ability is not an essential characteristic of a leg.
If lame legs are legs, so is a tail.

But a wounded leg is still a leg. Repair it, and it will function as
one. If it cannot be repaired, this fact does not change the kind of
thing it is. It is a leg, though damaged. The tail remains a tail.

The call for same-sex marriage involves a similar misdefinition.
Marriage is often characterized today as follows: (1) two people (2) who
love each other (3) want to perform sexual acts together, so 4) they
consent to combine their lives sexually, materially, economically (5)
with the endorsement of the community. Since same-sex couples can meet
the first four criteria, how can society refuse the fifth?

It is easy to see why this would be a cause of aggravation, not only
for same-sex couples who wish community endorsement of their
relationships, but for millions of others. If the criteria stated above
actually define marriage—and in contemporary Western society, many have
come to view marriage as no more than this—then refusal to acknowledge
and endorse same-sex relationships is a rank injustice, nothing but an
exercise in bigotry or stupidity.

Typically, marriage does in fact have these characteristics. But why
does marriage have these characteristics? Remembering why will help us
to remember how they show themselves in a relationship that has
the essence of marriage—and how that is often different in other

First, human beings have a powerful hankering to engage in sexual

Second, sexual intercourse between a man and a woman naturally and
frequently leads to children. Male and female alone each have part of a
complete reproductive system. Without both parts, reproduction cannot
happen. Without the result of children, it would be a real puzzler why
we have these organ systems at all, and why we have such a deep urge to
engage in sexual acts.

Third, the rearing of children is a lifetime responsibility. As
deeply social beings, we remain connected to each other across
generations. Even adults with children of their own need the wisdom and
guidance of their fathers and mothers. It is easier for those who enter
this project that they have affection for each other, and that they form
a self-giving friendship. To perform these actions lovingly is the
properly human way.

Fourth, because it leads to children, sexual intercourse has
extraordinary public consequences. It is not, as we might like to think,
a purely private act. It matters a lot to the community who is doing
it, and under what circumstances. So the community endorses certain
sexual arrangements; others, which fail to abide by the fullness of
truth of human sexuality, the community rejects as unfitting for human
beings. To support those that are fitting, it offers the institution of
marriage. In marriage, the couple promises before the community to
fulfill this project through vows of fidelity and permanence, joining
their bodies and their lives to make the project work. The community
promises to give the couple the privacy to perform their sexual acts,
and care for each other; it further supports the family by means of
appropriate protections and benefits. It may be that others could
receive similar benefits for different reasons, but this is why benefits
accrue to marriage: to help the marriage project flourish.

If sexuality did not naturally bring us offspring, it is hard to
explain why it exists, whether you believe in a purely material
evolution or a loving designer of the universe, for it would serve no
purpose. If sexual acts did not naturally lead to offspring, it is just
as hard to explain how marriage would have appeared in human history,
for it would serve no purpose.

Religions may bless marriage, but they did not invent it. Because it
involves such profoundly important human realities, it is no surprise
that sex and marriage have religious significance. But sex and marriage
have existed as long as there have been human communities.

If we accept the misdefinition of marriage using non-essential
characteristics as the complete story, it would be impossible to reject
same-sex marriage. Given the whole truth, however, it is impossible to
accept it. No matter how superficially similar they are to real
marriages, same-sex relationships cannot function as marriages.

Today, marriages crumble, families are torn, society flounders. Why?
We are not living in the truth. We accept a bad definition of marriage,
acquiesce to almost any sexual arrangement, glorify the quest for sexual
pleasure, treat children as a means to fulfill our desires.
Overwhelmingly, research shows that rearing children in any other
environment than with both their natural parents is damaging. Sometimes
that damage is unavoidable, as when a parent dies, but we shouldn’t seek
it. And it certainly won’t help to say the impossible is real.

We need the truth. We need to fix the legs. Calling a tail a leg only
makes matters worse.

Stephen J. Heaney is Associate Professor of Philosophy at the
University of Saint Thomas in Saint Paul, MN.