That belief manifests as an instinct in humans has now been well documented. It is mainly in the field of evolutionary biology that much of the research into this instinct has been done, including by Dominic Johnson in his new book, 'God Is Watching You - How The Fear Of God Makes Us Human'. Of course, neither Johnson or other evolutionary biologists are touting an actual deity in which belief is invested, but rather a creation of the human brain that offers unique evolutionary advantages.
But religious belief, as in investing one's mental capital (to the extent of conviction) into a given religion's credos and dogmas, must not be confused with God belief. The conflation of the two is what leads many to think religious belief is wired into the brain. It is not. Rather the brain's temporal lobes are predisposed to supernatural beliefs in general, whether devils, angels, ghosts or vampires. Johnson himself argues that belief in supernatural forces (and especially an "angry god") that can punish is a useful evolutionary adaptation in that it can steer adherents toward moral probity and societal cohesion, progress.
How come? Well, while rape for instance, might have enabled primitive, amoral tribes to spread their genes indiscriminately, once language and a god-fearing culture developed the putative presence of an invisible and angry monitor would have prevented tribe members from incurring high social costs. Also, it would save the tribe social capital by having to decapitate so many offenders if the invisible censor in the members' brains was already eliminating potential vicious acts before they could manifest.
Johnson himself also argues that god-fearing societies with high moral senses would also be more likely to be established and grow given they'd more likely punish even minor offenders. For example, he argues that societies that punish cheaters more consistently and aggressively are more likely to prosper. This can also explain why so many of these god fearin' societies have little tolerance for atheists, especially in holding high office. Johnson quotes the 17th century English philosopher John Locke, for example:
"Those who deny the existence of the Deity are not to be tolerated at all. Promises, covenants and oaths, which are the bonds of human society, can have no hold upon or sanctity for an atheist"
Of course, this is all bare balderdash, with Locke merely invoking another form of the ignoratio elenchi fallacy. Generate a false premise, i.e. "atheists deny the existence of the deity" (which we don't, we merely withhold investing belief in an unproven entity) and ergo we will have no truck for oaths, promises and covenants. But this is also a non sequitur even if some hard core atheists did "deny" a deity, because the rejection of bonds and covenants would militate against their own self interest!
But again, there is no real deity only a concept of one, what we call a "God concept". If religions or religionists claim they are advancing the SAME God but in different ways, then the critical thinker must point out the redundancy and superfluous nature of most. Since they will never agree on whose God meets that standard, then we must come back to the notion of relative and subjective God concepts.
The use of the term God-concept then recognizes implicitly that the nearly universal allegiance to some God belief or other is separate from the issue of any factual existence of a deity. In other words, the widespread use and appeal of God concepts does not mean that there is a genuine correspondent in reality. In fact, humanity's penchant for creating Gods via God-concepts is fully explainable by appeal to brain architecture and tendencies such as described by Michael Persinger in his monograph, The Neuropsychological Bases of God Beliefs, 1983. As he noted therein:
"The God Experience is an artifact of transient changes in the temporal lobe”
But that doesn't mean it isn't evolutionarily useful. Persinger was merely among the first to recognize that human brains possess a hyperactive agency detector device, thereby seeing unseen "agents" - spirits, demons, angels, gods and the like in natural phenomena as well as random happenings. (I.e. a person come through an airplane crash unscathed and insisted "God was protecting me!" - but somehow in his infinite power missed the dozens of other passengers.
As for natural phenomena, like solar eclipses, powerful lightning strikes, tsunamis etc., it was to be expected primitive humans - before the advent of modern science - would latch onto supernatural agents as the primary causes. They had no theoretical or rational wherewithal to come up with anything else. Still, as Johnson puts it:
"Learning religion is part of human nature. Learning science is against human nature"
Especially as much of modern science (e.g. quantum mechanics) goes directly against our dictates of common sense and simplistic versions of causality. Our basic nature is to use these as guiding standards but in QM and relativity, for example, they are useless.
As Johnson and many of his peers have noted, there is little harm in reacting to something that turned out not to exist but dismissing an unseen agent causing rustling in the thick brush might have dire consequences. Those primitives that ignored it might become meals for a saber tooth tiger. So, no surprise that the benefits of survival would be mutated to a pattern of evolutionary selection in seeing agents everywhere. I mean, hell, the instinct is even easily triggered in atheists. How many times have we walked down dark city streets late at night, and suddenly heard a noise behind us, then picked up our pace? Maybe not a goblin, but could be a mugger.
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All of which discloses that perhaps there is something to be said for controlling the belief instinct in certain venues - whether of politics, our modern culture, or psychology. If then belief is allowed to run amuck, say whether in unhinged paranoia (such as circulated on Alex Jones' "Info Wars"), or in accepting all Muslims are terrorists, or in supernatural cataclysms (e.g. the Armageddon fantasy) then we may pay the price. In the latter case , for example, if Ted Cruz seriously believes in Armageddon and that - if elected President- he has the power to bring it to fulfillment, we may all be in serious trouble.
But even in less serious or intense scenarios managing the belief instinct can prove valuable..