There are three major schools of thought concerning the importance of secularism, each with its own problem of internal inconsistency in either concept or practice.
The first school believes that secularism is necessary because of the diversity of religious beliefs. To keep the peace and serve everyone’s interests, we must not favor any one set of beliefs over others.
The second school believes that secularism is necessary because it prevents legislation that is based on unproven or even unprovable beliefs in the supernatural, which can lead us astray in the physical world that we share. Moreover, opening the door to one religion opens the door to all religions, since they all have the same faith-based justifications.
The third school simply believes in the separation of church (not religious belief) and state, such that no religious institution can dictate the course of the country and no government can dictate the beliefs and behaviors of a religious group. Such a policy supposedly allows religious liberty to flourish.
The trouble with the first school of thought is that religious beliefs are not a special class of belief, such that we can cleanly separate them from other kinds of belief in order to avoid playing favorites in government.
A government inevitably makes decisions based on a set of beliefs that only some of its country’s citizens share. If it is fair to ignore religious beliefs in order to respect diversity and maintain the peace, surely it is acceptable to ignore non-religious beliefs for the same reasons, since they are just as or more diverse and can be held just as fervently as any religious belief.
We say, for example, that the legality of abortion should be decided entirely on secular grounds because some people do not accept Christian reasoning and therefore should not be expected to follow it. But the same could be said about non-religious reasoning. If we banned abortion on the ground that even a zygote is a person who deserves rights (without appealing to any religion), many people would reject the reasoning. Why should they be expected to follow it?
Moreover, it is unclear what constitutes a religion, a religious belief, or a religious belief that ought to be absent from the workings of government. Is conservatism a religion? Is the belief that people have intrinsic value religious? If I develop a belief in the value of humanity because my religion teaches it, should I discard it when I legislate?
The trouble with the second school of thought is that supernatural beliefs are not necessarily religious beliefs and religious beliefs are not necessarily supernatural beliefs. An atheist who is completely disconnected from any sort of religious institution can believe in souls and ghosts; a Christian can believe in the value of love–a perfectly natural phenomenon–because of his religious upbringing.
It would therefore be more appropriate for this strain of secularism to oppose supernatural beliefs across the board–not just those reinforced by religion, which is but one source. But this means that secularists need to confront some hard truths about common beliefs within their own ranks. Intrinsic value, natural rights, and other conventional ideas about morality, for example, are popular but unsupported by evidence or logic. Some of them are, in fact, illogical. It is no more appropriate to ban abortion on the ground that the zygote has intrinsic value (or legalize abortion on the ground that the mother has a natural right to decisions about her body) than it is to ban abortion on the ground that God forbids it.
In short, secularists should not exercise a double standard that condemns one set of supernatural beliefs on the ground that they are unproven or unprovable even as it promotes a set of similar beliefs. For the sake of consistency, these secularists should be naturalists.
The trouble with the third school of thought, which is the narrowest in focus and thus perhaps the most popular, is that governments and religions inevitably conflict, at which point one must triumph over the other.
Allowing religious desires and beliefs to trump the law sets a dangerous precedent: one can simply claim that he has a “religious opposition” to the law to avoid having to obey it. In fact, since taxes are used to fund programs to which we might object, we could even avoid paying taxes.
Moreover, since religious beliefs are not unique, it is inconsistent to allow religious groups to ignore the law while forcing everyone else to abide by it. If a theist can avoid conscription, for example, on the basis of a religious conscientious objection even though religious beliefs are not special, then anyone should be able to avoid conscription on the basis of a conscientious objection, whether religious or otherwise. Elevating one set of beliefs–and thus the group of people who hold them–above the law for <i>no good reason</i> is unreasonable and unfair.
Every movement should understand its own motivations, establish its goals, and try to account for the consequences of its reasoning and of accomplishing its goals. Each of these three major schools of thought within secularism seems to be lost in at least one of these regards, mostly because each retains some naive belief in the peaceful coexistence of religion and secular government or in some essential quality of religion that separates it from other belief systems. The truth is that religion and secular government can only coexist to the extent that they are of like mind or if one cedes to the other–and that religion ought to be treated like any other belief system: according to the truth and value of its claims.