The prospects for successfully arguing that religious belief is worse for us on the whole than not believing are dim. We just won’t be able to get any clear, total picture of the positives and negatives associated with it, and even if we could, the question of associated benefit and harm is separate from the question of truth.
But our general affection for religion and the powerful, irrational urge we have to be religious often make it hard to us to see some really obvious downsides. Consider all the personal pain and ruined personal relationships that disagreements over religion have caused.
How much strife has there been between parents and children, friends, and family over differences of religious opinion? The amount is staggering. How many times has a father or a grandmother disapproved of a son or a granddaughter’s lack of religious piety? How many times have a son’s parents disapproved of his choice in a girlfriend because she is not of the right religion? How many love relationships have been ruined by the tension? How many marriages have been ruined by religious differences? How many children have suffered by being torn between parents bickering over whether or not to go to church, or which church to go to, or what they think about God? How many times has a son or daughter been heartbroken, lonely, or rejected because mom or dad disapproves of them on some religious grounds?
I suspect that there is hardly a single family in the United States where there have not been fights or emotional strain to some degree over religion. In lots of cases, family members get estranged and don’t speak for the rest of their lives. Relationships that are vital for human flourishing get completely destroyed over petty, pointless disagreements that are based on complete fictions. A person ends up being cut off and even despised by the people that they need and love the most over ideas that have no basis in reality.
Over the course of centuries, the amount of this kind of absurd suffering adds up to unimaginable levels. But since these sorts of harms are not the kind that will end up on the news, or get talked about openly, they remain hidden from view. The obvious question in all of these cases is, which is more important in the big picture—your relationship with your son, daughter, mother, or father? Or your adherence to a religious idea? Your marriage? Or a religious principle? The person you love? Or a religious impulse? The extended family relationships that a human needs to be happy? Or a religious idea?