My hypothesis is that, according with evolutionary game theory, the collective sacrifices are needed for the coordination of societies that are not formed by clones, like the human society. Such sacrifices can be in the course of informal (celebrations) or formally recognized as sacrifices in religious rites. (search also for "robotic truth" in this blog, where I explain how even the mere notion of what is Truth is mediated by this need for coordination).
It is in our instincts and we naturally arrange our behavior to do so. It is very interesting what happens we invite friends to a celebration. We sacrifice our time and money and dedicate out attention to the others mutually. Even the mutual perception of happiness being together assures everyone that the others prefer to be with us and invest their effort with us.
Probably, the less formal the sacrifices are, the less efficient are, and the sacrifice higher. I suspect that in really bad times and when the traditional rites have been forgotten, and people does not trust the formal institutions, the only alternative are human sacrifices. That happens in marginal groups of modern societies. We have to investigate these matters urgently (more on the reasons for this below)
To understand the mechanism by which sacrifices work for social coordination is the key: By making a clear and evident personal sacrifice in a public celebration is a sign of proclamation of commitment to the community because if we change to other community, we have to perform a second sacrifice for the other community. So we will have no incentives to defect if we invest in our group doing sacrifices. By making the sacrifice in public, we do not only accept our group. In ecumenic societies like this, that means also the public rejection of other groups. That's why secret societies, that do not celebrate rites in public, the sacrifices are higher: the latter does not happens and defection is easier, so the penalties for breaking the rules must be higher.
It is like the insurance companies (or by the way, the state run taxation and services system): There is an initial payment, a periodic payment and a payment if you want to leave. You can not receive the services of your insurance company immediately. You either have to pay more at the beginning or you have to pay a number of times before using the services. If you leave, depending on the services you demanded, you have to pay a penalty. Religious celebrations and sacrifices are the same, but at the instinctive (emotional) level. It is regulated by unconscious coordination mechanisms, while the insurance companies uses the same game theoretical logic (I can bet that insurance companies use game theory a lot), but it is perfectly conscious and rational. not instinctive. I have no emotional attachment to the other clients of my insurance company.
Paying taxes I do not find to fit with an intuitive notion of sacrifice, I mean it is not experienced as sacrifice because the money is not a natural (i.e. ancestral) possession towards we have a natural way to evaluate the gain of loss of it. Moreover it can not be made evident to the other people in a public event, that is the essence of the rite or celebration, in which mutual trust is created.
Probably the sacrifice of a marathon in a public event is much more fulfilling for this purpose than money. When, In a celebration, I spend money to make my friends happy, it is my time and my effort what constitutes my sacrifice, not the money. Women usually do not appreciate the amount of money spent by the husband in a gift, but the overall continuous personal effort invested on her. The sons of parents that do not spend time with them have the same psychological problems, no matter the amount of money the parent spend in material goods for them or either if they are rich or poor.
Probably this is because the evaluation of sacrifice of the other is hardwired to consider some kind of goods that actually were present in the ancestral environment: personal effort, and personal pain mainly. or some goods that were a product of personal effort: the blood of hunted animals or other basic possessions like the own blood, or some symbols that represent them, wit decreasing levels of realism. For example an animal bough for a certain amoun of money(but not the same amount of money as such). Anoter gift offered in sacrifice could be whatever that hurt adversary groups ad hurt ourselves in case we leave the group.
A country is something in the middle. But the emotional attachment for your country is not a consequence of the money you pay in taxes for the education system. It is because your celebrations and memorials and the history books, you read and all the things that you find easy to do with the people of your country and not so well with other people.
The dynamic of religion and sacrifice becomes clear when compared with an insurance company: when trust grows and the people don´t lie to the insurance company the payments become lesser and lesser. When the distrust increase, and the demand of payment grows by liars or wrongdoers, the payments grows until the payment is comparable to the service. That is, if the clients have a false accident of total loss every year,, the company will demand the price of a car every year. if you kill people and expect that the group will help you with their lifes from the probable vengeance, it is expected that your group demand for you to kill one of your children in public or to kill two enemies or to take prisioners for killing them in the altar or some equaly horrendous. Otherwise the game theoretical equilibrium will not work to stabilize the group cooperation. That`s what happens in ancient and modern tribes.
What I say is that atheism is NOT an option.
Not only because Chesterton said that anyone who does nor believe in God will en up believing in anything, but also because that is in the structure of the human mind as is know by personal introspection (the greek philosophers), historical experiience (any religion-less community that lasted?) and by game theoretical+ evolutionary reasons that i tried to explain here.
At the moment that you reject a deity, you accept other. The religion of atheists is quite similar to a primitive religion because religion emerges in its primitive form when you reject your own.
But the human mind can not work with impersonal myths. Whenever impersonal myths are created, exist also personal entities that become myts. Normally the ones that created these myths of fighted for them.
The most primitive form is the cult to the personality, that is the cult to a living god-man. Who was the leader of the tribu, whose actions are mytified and celebrated. Of course this is the worst of all kinds of religions. That happens ever when a society tried to establish itself in abstract principles, being them comunism, equality, progress, rule of law, evolution etc.
As an example, after the cult to Hitler, Marx, Stalin, Mao, Kim Jon II, Castro.. and many others.. the modern cult to Darwin
Incidentally the reason why the cult to Lincoln, Jefferson etc is so weak is because the American constitution IS a constitution under a personal God.
I´m astonished contemplating how people can contemplate with horror the belief in a god that they thing that it does not exist and accept the belief in worldly lies and praise completely invented myths about their favorite heroes. Even if they know that are false. That Kim Jon Il wrote a mean of tree books a day is incredible for them but there are equally fantastic histories and Myths widely believed that would make Chesterton crap up. And North-coreans too.
The wishfulthinker fall in tears when pronouncing his sacred capitalized worlds: People, Democracy, Equalty Human Rights and so on. In the past, Socialism, Worker Class and such craps motivated the same heart lifts. Today even the Terrorists invoke what they call "Democracy" with passion.
But in his country, like in any other, the same families alternate in government, with a few exceptions, no matter the kind or regime and the political party. All are equals except that some are more equal than others. Perhaps things are closer to the Ancient Regime rather than to the myths of his utopic society. The more the utopics are in power, the more the ancient regime (that they had in the imagination) returns. Perhaps all such elevated concepts are not part of the reality but ideological constructions and their most known advocates, are nothing but just power seekers that may expect the worship of the wishfulthinkers?
I repeat the cult of men to men is the most primitive and dangerous religion. And RELIGION CAN NOT BE AVOIDED: you can not live without a form of religion, like you can not live alone.