Widespread love and peace?
Let's be real first before I talk about the "outcomes of atheism." Institutionalized Christianity is roughly 1700 years old now, and the movement itself approaches its second millennial. That means that Christians have had a rather long time to start demonstrating their ability to manifest goals like peace and love in the world. Frankly, it's not going too well, and however well it is going now is primarily in spite of the doctrines and dogmas of Christianity, whatever they want to claim Jesus said, and not because of it.
Consider, for example, the Inquisition. "Believe as we do, or we'll do you the 'favor' of torturing you until you say you do, confess to imaginary crimes you didn't commit, and then publicly gut you or set you on fire as a warning to everyone else," it effectively said, presumably under the banner of achieving those two outcomes. We can presume that their reasoning included the idea that if everyone believes the same thing, there may be far less reason for strife (particularly when the sources of the beliefs are strictly controlled as they were at the time--it was still a capital crime and supreme heresy to possess a Bible in any vernacular language of Europe), and if heretics confess their sins and come to Jesus, they get to go to heaven--and in either case serve as a useful example for others to follow concerning how serious the matter of getting into heaven is. The frightening bit is that this entire affair can be warped via Christian doctrines into being part of "love" (and the infamous Westboro Baptist Church does exactly this to justify their protests), largely thanks to that threat of hell and "promise" of heaven. And so we might wonder if this is what is meant when Christians say that the outcome of Christianity is widespread love. I'll take my chances without that, thanks.
What stopped the Inquisition? Society at large decided it had had enough, and that arm of the Church was revealed for what it was: horrible. It is exactly what we expect to see from a totalitarian organization built upon patently bogus nonsense, though, and it only stopped doing that when it lost the power to do it.
The Inquisition is hardly the only example of the doctrines and dogmas of Christianity run amok, causing immeasurable suffering before society at large corrected it. This process has happened due to secularization, regardless of whether or not a less brutal sect of Christians led the charge, as secularization is a process by which the strictness of the sect is loosened. As people read their Bibles for themselves, once King James put them out in tongues people understood, they saw many of the horrors contained within that Bronze Age collection of stories, and they saw them for being patently incompatible with anything resembling civil society. This process continues today, largely because the United States is so powerful, so modern, and so outlandishly religious, and too slowly but steadily the nonsense is beaten out of the religions, the society becomes more secular, and people view more and more of the scriptures at their cores as being, at best, admonishments for a time gone by. Slowly, sometimes centuries too late, the religious institutions themselves come around and change their beliefs--as was seen quite clearly in 1978 when the Mormon Church claimed a "revelation" that God no longer curses people with dark skin.
What about widespread peace? This is surely a bit of a joke, right? At the centers of these religions, since they are no longer truly accepted as explanatory constructs for everything (thank you, science), there are many veils that just barely cover a set of sincere and meaningful fears. Those fears are only successfully covered when there are no other competing ideas that threaten to lift the corner of the veils, revealing them for what they are. Christians (to say nothing of other religions) have a demonstrably hard time agreeing upon much of anything about their religion, and there are literally tens of thousands of denominations that prove this. Churches--particularly Protestant ones--split like racked balls in a pool hall, effectively creating new sets of doctrines that represent the "true Christianity." Over time, these become serious enough to where some denominations recognize others as being false religions, and if these folks were to sit down and compare notes, again about what gets someone to heaven and hell in the main, they'd get along far less than they do now, which is mostly another result of secularism and the cultural tolerance that comes with it (in addition to a perceived need to be more unified against a rising tide of non-religious life).
In short, we shouldn't necessarily trust the "widespread love" and have no reason to expect the "widespread peace" that Christianity claims to seek as an outcome. Like every other article of faith, there simply isn't any evidence to warrant them. It is worthwhile to note, before moving on, that this belief in heaven and hell is something of the key that drives truckloads of these problems into religious thinking (making such beliefs consequentially unethical).
"Atheism" isn't what they think it is.
Another important point to make here, and again and again and again apparently, even to atheists, is that atheism is not a thing. This point cannot be overstated. Atheism is a lack in a certain kind of beliefs, and it doesn't have a "goal," though widespread atheism would have an "outcome." Now, there are "things" within atheism, meaning movements with goals. In the linked article, I mentioned two primary ones, but I can add to that now that I've thought about it more:
- The Secularism Movement: This is a movement to advance secularism, which means primarily to remove religion from the public square (meaning government, not people being individually religious in public). Many religious people are also secularists, so it's not limited to "atheists." A major goal of this movement is to remove all religiously motivated legislation from the law books of a modern, advanced, secular society.
- The Freedom From Religion Movement: This is mostly a wing of the Secularism Movement, and its primary goal is to ensure that everyone in a secular society is as free from the influences of religion as they want to be. This movement particularly seeks to keep religion and state separate. Though more atheists see this as important than do religious folks, largely because of the discrimination we face in an overly religious yet "free" society, minority religions are often involved in this as well.
- The Out Campaign: This is yet another wing of the overarching movement for secularism, and this one focuses on getting nonbelievers "out of the closet," i.e. to get them to be unashamed to be who they are openly. Since "atheists" are rather discriminated against and because there are heavy family and social pressures to conform to the religious beliefs of family and peer groups, the Out Campaign seeks to help closeted atheists and agnostics be open about their lack of beliefs. This group also has the goal of making it more clear that nonbelievers aren't alone, as many of them feel, particularly throughout the Bible Belt of the U.S.
- The Secular Humanism Movement: Secular humanism is as close to a religion as atheists usually get, but unlike religion, it is actually a moral framework. The idea here is to promote humanism in a secular society, where humanism is a philosophy that good is served by advancing the cause of humanity. Many secular humanists extend this notion to other species as well as human beings.
- Project Reason: This is less a movement and more a nonprofit with the goal of promoting logical and scientific, as opposed to authoritarian and ideological, thinking.
- Other endeavors that have goals that are common to nonreligious people (and also to many religious people) are science advocacy and rational skepticism. These, like Project Reason, primarily aim to enhance evidence-based thinking. They are identifiable with "atheism" because religious faith is, by definition, not evidence-based thinking, though many religious people are science advocates.
The outcome of atheism
The outcome of atheism--in context meaning what we can expect if a vast majority of people (or everyone) were atheists--can be seen by considering what the functional difference between atheism and theism is: a lack in belief in gods. Gods are a particular class of pseudo-explanations for phenomena, ones that happen not to have any evidence to support them. Belief in gods, i.e. theism, amounts essentially to accepting these pseudo-explanations on insufficient evidence. Widespread atheism, then, would remove the acceptance of this class of pseudo-explanations.
It's not entirely fair to say that an outcome of atheism would be a society that is more evidence-based in its thinking, but in a way, that's exactly what would happen. One enormous and influential class of non-evidence-based thinking would be removed from the situation. That would leave us, in terms of explaining things, with evidence-based science and non-evidence-based pseudoscience. It's difficult to say whether or not we would be more rational as a result (I actually doubt it), but this is still enormously significant.
Why is it significant? Flash back to the earlier parts of this post to get an idea--people are more serious about religious beliefs than they are about pseudoscience. It is not uncommon to hear of religiously motivated violence, even murders and wars, but it is incredibly rare to hear about such things that were inspired by astrology, energy healing, or homeopathy. The cores of pseudoscientific constructs are not as poisonous as the cores of religions. Of course, this is because the fears that religions attempt to paper over are so much more powerful, but in a purely atheistic society, there would be much more motivation to help people cope with the hard facts of being a living consciousness in a mature and healthy way instead of attempting to cover them up with exclusionist nonsense and outright lies. Indeed, perhaps the reason we don't have good coping strategies for these difficulties already is because we've been so freaking religious that we've never attempted to actually deal with the problems.
This is the outcome that many atheist people seek, although most would frankly be satisfied with people keeping their personal beliefs to themselves and out of legislation (Freedom from Religion). The evidence is abundance that God doesn't provide us with "widespread love and peace," and even if we cannot do that for ourselves, we can at least remove some of the most problematic pieces of our violence puzzle.
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