In a democratic country, people are free to belong to any religion (or none) as they wish - this is the human right of freedom of belief1. To remain just and fair, governments should be neutral when it comes to religion - secular. In liberal democracies, rules should apply to all people fairly and equally regardless of religion2 as much as possible. History has shown us that if the state encourages, officially represents or enforces just-one-religion then it always creates enduring social inequalities and infringes upon the basic human right of being able to choose religion and beliefs freely1, which over time is destabilizing. Therefore, for both ethical and practical reasons, politicians and government officials should not be under the control of religious institutions either formally, informally or symbolically2. This preserves equality and fairness to the maximum extent, except for those who want to impose their beliefs or practices on others, allowing for a reasonable, fair and tolerant society.
Secularism, promoted by secularists, is the belief that religion should be a private, personal, voluntary affair that does not impose upon other people. Public spaces and officialdom should therefore be religion-neutral. Secularism ensures that religions are treated fairly and that no bias exists for a particular religion, and also that non-religious folk such as Humanists are treated with equal respect. It is the only democratic way to proceed in a globalized world where populations are free to choose their own, varied, religions.
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Freedom of Religion and Freedom of Belief are upheld in Article 18 the United Nation's Universal Declaration of Human Rights3. It affirms that it is a basic human right that all people are free to change their beliefs and religion as they wish4. No countries voted against this (although eight abstained). This right was first recognized clearly in the policies of religious toleration of the Netherlands and elsewhere in Europe in the post-enlightenment era5 of the 19th century. In democratic countries, freedom of belief and religion is now taken for granted6. In 2016 a study found that over 180 countries in the world had come to guarantee freedom of religion and belief7.
Long-term studies have shown that religious violence and persecution both decrease in cultures where religious freedom is guaranteed8. Despite this, there still are many who are strongly against freedom of belief4, including entire cultures and many individual communities of religious believers. Their alternative is that you are not free to believe what you want and they often state that you cannot change religion without being punished (often including the death penalty): this is bemoaned as one of the most dangerous elements of religion9 and "the denial of religious freedoms is inevitably intertwined with the denial of other freedoms"10 and the solution is, everywhere, to allow religious freedom and the freedom of belief.
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Religious pluralism describes modern society, where people are free to follow whichever lawful religious practices they wish, and as such, the citizenry is comprised of multiple faiths and belief systems, as well as many who don't follow any religion. Where religious compete, conflict and impose on other people, how should the government respond - if at all?
Traditional Establishment: Pick one form of religion and keep it institutionalized.
Libertarian Grants or Laissez Faire: Adopt special religious rights and exemptions for all religions.
Secularism: Abolish all special religious rights.
2.1. Traditional Establishment: Should government pick one religion and institutionalize it at the expense of all others? Most modern governments have emerged from a history of such established religion: modern governments are attempting to be fairer, but are often at odds with strong remnants of conservative religious power, who see any attempt at creating equality to be "persecution" of themselves in particular. Picking one form of a religion over all others is clearly not acceptable in a world where acceptance of human rights means governments cannot force civilians to convert, and it is unacceptable to discriminate on grounds of religion.2
2.2. Libertarian Grants or Laissez-faire: This is where the government grants special rights to ignore some legislation if it contradicts beliefs, or declares complete laissez-faire (hands-off), wherein it won't intervene with any religious practice. But this ends up with fewer rights to those who are not religious. Also, religious folk come up with all kinds of requirements on behavior, including on those around them. It is generally not possible for ordered, mature society to allow religious people to adhere to all their religious rules - imagine forever having to avoid blaspheming against all of the world's gods, holy books, core beliefs - everyone would need to be well-versed in everyone else's religions and almost any act could be justified by claiming religious exemptions. Also, granting special rights to religious folk whilst not granting it to everyone is unjust. This route leads to inter-communal religious violence and constant prejudice against minorities (including women11) by dominant religions.
2.3. Secularism: We can drop the special benefits for religious beliefs. So, it is immoral to discriminate against gays on account of their sexuality. Therefore it is immoral even if you are a Christian: your religious beliefs do not protect you from having to uphold societal morals. Likewise, women are allowed to manage their finances, have jobs, and enjoy the same freedoms as everyone else, even if it's against the religious rules of some communities. Human rights has prominence over any religious rules, and, the legal system doesn't need to refer to any particular religions. The Rule of Law is a key cornerstone of democracy, wherein the law applies to all people equally - rich and poor, religious or non-religious. This creates a sensible, just and tolerant society. All exemptions are granted to everyone (if they are acceptable) or abolished.
Andrew Copson in his address to the annual Secular Europe Campaign in 2013, explained:
“What does it mean to live in a free and liberal secular democracy? It means if you don't like abortion, you don't have to have one. If you don't like gay marriage, you don't have to have one, or be a guest at one. If you don't like assisted dying for the terminally ill, you don't have to opt for it. But it also means that you can't enlist the state to force your preferences and prejudices on all your fellow citizens. Secularism guarantees our freedom of conscience and our freedom of belief, humanist and religious alike. But all over Europe there are groups of all religions lobbying [...] to impose their own values on us all.'”
There is a balance to be had between freedom of belief and religion (a fundamental human right) and good democratic governance, where religions are treated fairly, but also prevented from harming others. When religious ideas of morality and blasphemy are institutionalized by government, inequality is inevitable as other religions and beliefs are overlooked or even indirectly proscribed. When it comes to actions that cause suffering, the basis of the person's justification doesn't matter - all we are interested in is making it clear the action is not acceptable. Adam Smith argued that the way to achieve harmony between religious believers and others is for government not to interfere, except to oblige them not to persecute others12 - and this means that a neutral, central state must enforce an overall set of minimal independent values. Human Rights are of course the clearest way to enforce a fair playing field so that a multiplicity of religious groups can exist together.
“Religious beliefs... deserve protection [but] religious conduct, on the other hand, may sometimes require limitation.”
Kressel lists "the enshrinement of religion in the fundamental rules of the state" as one of religion's most dangerous attributes (out of three)9. Many countries grant that laws that protect religious belief also protect non-belief - the UK has had such secularist law since 200614, and in late 2016 the USA also adopted this stance15. "Secularism" is the idea that in order to treat people fairly, all special religious rights should be abolished as democracies should not legislate on beliefs, but on actions (regardless of religion). The government passes laws because it is necessary and because it is for the greater good. The more exceptions there are to those laws, the more democracy is weakened. Legislating for special religious rights are a travesty of justice and undermine democracy and the common good. It is rarely required to mention specific religions in law, or to exempt them from law. Things are better than they've ever been, but few countries so far have managed to achieve complete impartiality and fairness towards religions
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It is not a Human-Rights requirement that governments are secular. It is best-practice democratically, in order to prevent bias, but, it is feasible that a well-natured government could be both openly religious, and, could treat all of its citizens equally and without forcing upon them religious rules - that is - rules and laws derived from the government's own religious beliefs. But never in history has this occurred. Even today, there is not a single example of a country whose government is openly Jewish, Christian or Muslim, and which governs in an unbiased manner towards members of the 'wrong' religion. Thankfully, most democracies have moved steadily towards the secularist position that the public sphere should be neutral in terms of religion.
These principles were put succinctly by Thomas Jefferson after witnessing the troubles involved when colonies attempted to combine government and religion: he said there should be a "wall of separation between the church and state"16
“The Comparative Constitutions Project at the University of Texas at Austin in the US has documented and assembled the constitutions of nearly every independent state in the world. ... in 2016... over 70 of the 195 constitutions declare a separation of religion from the state... over 180 of them guarantee freedom of religion or belief.”
The separation of church and state inherently leads to greater tolerance between religions, as it is no longer possible for sects to battle against each other for power and authority, as it is not possible to formally achieve either, and, society is led into a situation where power-battles and prejudice are not tolerated.17
Having established religions as part of formal government results educational and cultural skew, which will prevent many people from ever being able to judge the world's religious in a sensible manner. Thomas Paine puts it thusly:
“The adulterous connection of church and state, wherever it had taken place, whether Jewish, Christian, or Turkish, had so effectually prohibited by pains and penalties, every discussion upon established creeds, and upon first principles of religion, that until the system of government should be changed, those subjects could not be brought fairly and openly before the world.”
These feelings are borne out by the facts. After analysing international statistics on this topic Grim & Finke concluded as follows:
“[There is a] strong relationship between violent religious persecution and government's selective favoritism of some religions above others. The more severe level of persecution ... is present at two-and-one-half times the rate in countries where governments show obvious favoritism to some or one religion.”