The problem with the "atheist" moniker has been recognised for decades. It's too negative, too associated with amoral nihilism. It's understandable then that many would agree with Richard Dawkins that we need a word like "gay" which "should be positive, warm, cheerful, bright". So why not "bright"?

One reason, which I mentioned right at the start of this series, is that it sounds too smug. But there's an even more important reason why we should not choose a word that is "positive, warm, cheerful": although many atheists are all those things, atheism itself is none of them.

Atheists have seemed rather keen in recent years to stress their jolly side. As well as the whole "brights" movement, there's the "happy human" logo used by the International Humanist and Ethical Union, the British Humanist Association and several other humanist groups. Then there were the atheist bus posters telling us that we should stop worrying and enjoy life.

Given how the atheist stereotype has been one of the dark, brooding existentialist gripped by the angst of a purposeless universe, this is understandable. But frankly, I think we've massively overcompensated, and in doing so we've blurred an important distinction. Atheists should point out that life without God can be meaningful, moral and happy. But that's "can" not "is" or even "should usually be". And that means it can just as easily be meaningless, nihilistic and miserable.

Atheists have to live with the knowledge that there is no salvation, no redemption, no second chances. Lives can go terribly wrong in ways that can never be put right. Can you really tell the parents who lost their child to a suicide after years of depression that they should stop worrying and enjoy life? Doesn't the appropriate response to 4,000 children dying everyday as a direct result of poor sanitation involve despair at the relentless misery of the world as well as some effort to improve things? Sometimes life is shit and that's all there is to it. Not much bright about that fact.

Stressing the jolly side of atheism not only glosses over its harsher truths, it also disguises its unique selling point. The reason to be an atheist is not that it makes us feel better or gives us a more rewarding life. The reason to be an atheist is simply that there is no God and we would prefer to live in full recognition of that, accepting the consequences, even if it makes us less happy. The more brutal facts of life are harsher for us than they are for those who have a story to tell in which it all works out right in the end and even the most horrible suffering is part of a mystifying divine plan. If we don't freely admit this, then we've betrayed the commitment to the naked truth that atheism has traditionally embraced.

Of course there are some atheist worldviews that do claim to provide a bulwark against the worst that life can throw at you. In particular, there is the stoicism that teaches us to take mortality and the impermanence of all things as cues to detach ourselves from the ups and downs of life and embrace an accepting tranquility. But first of all, it's not clear this really does make sense in a completely naturalistic framework. For the ancient stoics at least, this only made sense in the context of a metaphysics where reason was part of the divine. More importantly still, this is only one view, and most atheistic outlooks contain no such consolations.

Even more disturbing, perhaps, is the threat of moral nihilism. Atheists are quite rightly keen to counter the accusation that life without God cannot be moral. The British Humanist Association, for instance, claims that "Right and wrong can be explained by human nature alone and do not require religious teaching". But, just as with happiness, there is a need to distinguish the possibility of atheist morality from its inevitable actuality. Anyone who thinks it's easy to ground ethics either hasn't done much moral philosophy or wasn't concentrating when they did. Although morality is arguably just as murky for the religious, at least there is some bedrock belief that gives a reason to believe that morality is real and will prevail. In an atheist universe, morality can be rejected without external sanction at any point, and without a clear, compelling reason to believe in its reality, that's exactly what will sometimes happen.

So I think it's time we atheists 'fessed up and admitted that life without God can sometimes be pretty grim. Appropriating the label "heathen" is part of this. Heathens are unredeemed outcasts from heaven who roam the planet without hope of surviving the deaths of their bodies. They may have values but they are not secured by any divine source. Yet we embrace this because we think it represents the truth. And so we don't just get on and enjoy life, we embark on our own intellectual pilgrimages, trying to make some progress in a universe on which no meaning has been writ. The journey can be wonderful but it can also be arduous and it may end horribly. But there is no other way, and anyone who urges you to follow a path that they promise leads to a bright future is either gravely mistaken or a charlatan.

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