The right to obey one’s conscience is widely considered the ground for religious liberty and has been treated as such for centuries. Martin Luther protested that “to go against conscience is neither right nor safe” when he was ordered to recant at the Diet of Worms; John Locke promoted similar ideas in his A Letter Concerning Toleration; and James Madison once wrote, “Conscience is the most sacred of all property.”

Conscience as the foundation of religious liberty is still upheld today. Robert George, one of the foremost defenders of conscience and religious liberty in our time, writes this in Conscience and Its Enemies:

The natural-law argument for religious liberty is founded on the obligation of each person to pursue the truth about religious matters and to live in conformity with his conscientious judgments.

It is typically assumed that invocations of conscience and religious liberty are the sole province of Christians and members of other faiths. More precisely, conscience is usually invoked in order to defend the right of religious believers to not commit certain acts.

However, a possible problem with conscience is that it can just as easily be invoked by those who profess to have no religious beliefs at all.

If this is the case, then the idea of conscience may not be enough to protect the freedom of Christians (or adherents of any other religious traditions) to live in a way that is at odds with popular morality. If conscience is pitted against conscience, then the side with the greatest number of supporters (i.e., the non-religious group) will decide whose conscience is honored.

This point is elaborated in Jonathan Leeman’s Political Church – a book whose larger argument concerning the nature of the local church as a political institution is made in such breadth and depth that I cannot hope to replicate it here—and I am indebted to his work in forming this discussion focused on the topic of religious liberty and conscience specifically.

Conscience as a “View from Nowhere”

The reason conscience became the almost universal ground for religious liberty in the first place, Leeman writes, is that the idea of conscience does not have any particular theological or religious content to it:

Conscience proves a useful concept for religious freedom because, unlike religion, it seems to be a universal concept—most would agree that they have one and would prefer for it to remain unmolested.

Precisely because conscience is seen as something that everyone has (and has an obligation to follow), it enables religious believers to defend their exercise of religion on a mutually accepted ground:

If religion is a property of conscience and both believer and unbeliever share one of those, then the believer can convince the unbeliever to respect his or her religion.

But consider the implications of conscience acting as a neutral, publicly accessible concept. If freedom of conscience is claimed by both religious believers and non-believers, then the idea of conscience does not necessarily entail a belief in God. Otherwise, non-believers would not claim to have a conscience they must follow.

To what moral authority, then, do non-believers appeal when they invoke conscience? If there is no God, then it can amount to nothing more, says Leeman, than “the whims of whatever ideologies rule the day”:

The doctrine of religious freedom [based on conscience] becomes unaccountable to any standard of right, divine or otherwise. What’s to ensure that its philosophical services will be hired only by upstanding and virtuous monotheistic religions? What’s to prevent other parties and interests from employing it for ends besides the worship of God?

What’s to become of religious liberty if we stake it on conscience and those who disagree with us cannot, “in good conscience,” allow us to “discriminate” against others as we would if left to our religious liberty? As Leeman asks, “Why should the believer’s conscience count for more?”

Conscience Properly Defined

Do the people who invoke conscience against religious liberty do so legitimately?

Robert George certainly doesn’t think so. By his account, there are two definitions of conscience, the classical (true) one, and the contemporary one.

Conscience classically understood (as articulated by Catholic theologian and priest John Henry Newman) is,

One’s last best judgment specifying the bearing of moral principles one grasps, yet in no way makes up for oneself, on concrete proposals for action. Conscience identifies one’s duties under the moral law [emphasis in original].

Conscience rightly understood imposes duties on us. It is not, as George puts it, a “writer of permission slips. It is not in the business of licensing us to do as we please.” This is in contrast with the contemporary understanding of conscience, which is,

Concerned not so much with identifying what one has a duty to do or not do, one’s feelings and desires to the contrary notwithstanding, but rather with sorting out one’s feelings. Conscience as self-will identifies permissions, not obligations.

A second key feature of the classical understanding of conscience is that it is based on external moral principles. According to George, not only does conscience impose duties on us, the moral principles on which those duties are based must come from beyond ourselves.

We saw before, though, that if conscience is to be a universally accessible concept it must not entail belief in God. So if George’s understanding of conscience requires an external morality that comes not from ourselves (but not necessarily from God either), then to what can we turn for ultimate moral principles?

The answer is natural law. By this account, all humans can discern universal moral principles based on what George calls “basic goods”:

By reflecting on the basic goods of human nature, especially those most immediately pertaining to social and political life, natural-law theorists propose to arrive at a sound understanding of principles of justice, including those principles we call human rights.

George holds that to obey one’s conscience in the truest sense and arrive at “one’s last best judgment” involves the exercise of one’s reason. Under this theory, right reason will tell us that religion is a basic good that ought to be protected by religious liberty and that those who invoke conscience against religious liberty have erred in their reasoning somehow.

So in short, under George’s theory of natural law, there is a difference between conscience invoked rightfully and conscience invoked wrongfully. Will this distinction help protect our religious liberty?

The Limits of Rationality

Leeman acknowledges that George’s natural law account of conscience is coherent. Nevertheless, even if we can articulate a robust theory of conscience that ought to be universally acceptable, that has no bearing on whether others will in fact agree to it. Hence this last question from Leeman: “Will this strategy really work for the purposes of political persuasion?” Can we persuade others to accept this understanding of conscience?

As George notes, rationality itself—and thus, our conscience—can go awry:

We are…capable of behaving grossly unreasonably—especially when deflected by powerful emotions that run contrary to the demands of reasonableness….Even when following our consciences, as we are morally bound to do, we can go wrong. A conscientious judgment may nevertheless be erroneous.

If we cannot reason our way to a religious liberty that will be accepted by those who disagree with us, then what do we have left?