It is reasonable to be suspicious of the values and morals of someone operating with no moral code. It is also reasonable to be suspicious of someone who knows and can anticipate your moral code but refuses to disclose his own. I fail to see the cognative bias.
is not useful information, since the religious person will be more suspicious of
any out-group, regardless of the god (or lack of god) they follow.
Be careful of
attribution error. We have identified two reasons why the religious might distrust atheist.
1) In-Group Favoritism: The tendency of any group to favor members of their own group.
2) Moral Unpredictability: The difficulty one faces predicting and evaluating the behavior someone who keeps their value system 'closed source' aka undisclosed.
The next logical question to ask is how much does each factor contribute to the society wide distrust of atheist that was discussed upthread. To determine this we should compare opinions on atheist to opinions on competing 'open source' groups like Buddhism or Islam.
The discussed study describing distrust of atheist is not public and behind a paywall in the Journal of Personality and Social Psychology. However, the
news article about the study stated that study participants
believed atheist more likely to commit an immoral act (by failing to leave behind valid insurance information after hitting a parked car) than a Muslim. Even those with no religious affiliation felt this way.
The study appears to have been done in the west where Islam is non dominant and not particularly popular right now. Together these findings suggest that In-Group Favoritism is unlikely to be the primary driver of distrust towards atheist and that other explanations like Moral Unpredictability should be considered.
So let's return to your stated original argument.
I don't think any of these points come close to dismissing my original point, which is
It's more likely that religious people need religion in order to be moral actors, just as BADecker wrote.
The statement is correct it needs to be broadened and generalized.
It is likely that humans in general need a coherent internal code in order to live healthy and moral lives. For the religious this is provided by their faith.
I think most people understand moral codes such as "respect and treat others as you wish to be respected and treated", however those that belong to groups which make clear delineations between them and "outsiders" are likely to have some moral codes that are not acceptable to other inward facing groups, thus causing conflicts. Conversely, groups which are not inward facing and accept outsiders based on their actions rather than the actions of the groups to which the outsiders belongs are likely to experience less conflict and unhappiness than those that judge all outsiders with suspicion.
To say that a persons moral code is provided by a religion is a concern. Religious code can be reinterpreted by holy men, who can then shape a group's moral outlook to suit their particular views. By relying on religious dogma to inform your entire moral code you risk acting immorally, possibly even against your in-built moral sensibilities.
In summary: People who rely on their native or built-in moral code are more likely to have a positive affect on their local social group than people who rely on dogmatic moral strictures.