Does A+ represent the official atheist position on social justice?
No. Not all atheists are interested in advocating for social justice. Many atheists choose instead to focus on other worthy endeavors such as science education, skepticism in medicine, or the separation of church and state. Many atheists do not consider their atheism particularly important, nor do they necessarily connect their atheism to any other positions they do or do not hold. And even among those atheists who are interested in promoting social justice, not all agree that the issues focused on by Atheism Plus are the most important ones or that the supporters of Atheism Plus are addressing these issues the right way. There are as many perspectives on social justice, its meaning, its import, the current state of its various aspects, and how best to promote it (if at all) as there are people. All are welcome to start, support, oppose, or ignore groups like Atheism Plus. However, supporters of Atheism Plus are not obligated to provide a forum for their opposition.
What if I don’t want to participate?
Those who choose not to use the Atheism Plus designation are not automatically considered supporters of bigotry. An “us and them” understanding is implicit whenever a group of any kind forms, but the “them” in this case is not monolithic. It is composed of individuals and groups who range from the supportive but uninvolved, to the neutral, to those opposed on principle, to the unabashedly bigoted, hateful, and discriminatory. The “us” in this case are the individuals and groups who are interested in seeing what an association of atheists working against bigotry, hatred, and discrimination can accomplish when given their own spaces in which to develop ideas. This position should be understood as distinct from the “with us or against us” position endorsed by some early proponents of Atheism Plus–a position which has been rejected by general consensus. (Anyone who decides to do so may attempt to speak for Atheism Plus, but whether their ideas find any support with the rest of the group is a different matter.)
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Doesn’t Humanism cover this stuff?
Atheism Plus embraces humanism. One of the formulations of Atheism Plus is “Atheism + Humanism + Skepticism”. However, to quote an article from the American Humanist Association website, “the humanist movement has never considered atheism (construed as a rejection of all concepts of God) as a necessary part of the humanist outlook.” Such a rejection is a necessary part of the atheistic outlook. Humanism has a rich tradition of promoting ethical living, but many people interested in changing minds find that it does not adequately stress the reality that there are almost certainly no gods and that this is almost certainly the only world in which we will ever exist.