Perhaps it is ironic to accuse an atheist of Bad Faith, and it becomes doubly so when the origin of the term "Bad Faith" is considered. After all, the idea of "Bad Faith" is developed by Jean-Paul Sartre, one of the 20th Centuries foremost proponents of atheism. And yet, one of the most basic flaws of most modern atheism can best be described through understanding Sartre's view of metaphysics and human consciousness.
Although before I talk about "Atheism", to make it clear that I am not making a total strawman, I should point out that in philosophy there are two major strains of Atheism. The first, dating from Kant's critical philosophy ( Kant was himself probably not an atheist), is the continental or existentialist tradition. Methodically, it doubted the ability of human reason to understand God, and whether any defined concept of God could bring an end to human doubt. In its form, it is often poetic or literary, rather than being strictly philosophical. Secondly, there is English atheism, dating from David Hume up to the present day, where it is a cottage industry, including such celebrities as Richard Dawkins and Christopher Hitchens. The intellectual failings of English atheism will be the core of my argument. English atheism is based on skepticism of anything outside of "natural science". It is heavily interested in arguments about such things as evolution.
It should also be pointed out, and will perhaps lead to some diversion, to compare the two branches of atheism, continental and Anglo-Saxon, with the division between Catholicism and Protestantism.
Other than the fact that English atheism tends to deal with subjects that are not rational, but rather of a historical or perhaps even ad hominem character, such as historical errors or atrocities of church bodies, or personal failings of contemporary religious figures, it has a deeper failing in my eyes. And that failing is, as I mentioned at the start of this essay, the concept of "Bad Faith".
To explain a little bit of Sartre's rather complicated philosophy, "Bad Faith" arises when a person takes something that is "in-itself" to be a totality. To Sartre, simple objects, whether external (a cup) or internal (an urge), were "in-itself", meaning they were a totality. Actually, even calling such things a "totality" is a misnomer, because an "in-itself" can be neither complete or incomplete. It just is. But human consciousness, because it can understand "nothingness", can create a distance between the in-itself and the potentialities that surround it. We can, as it were, step back from the in-itself. And when we choose not to do so, we act in "Bad Faith". For example, someone who sells a gun to an outraged person and says that it is "just a transaction" is acting in bad faith, because they don't go beyond the "in-itself" of the act to the obvious consequences. A person who has a history of alcohol abuse who takes "just a drink" is acting in bad faith, because they are refusing to look beyond the simple act to its (once again) obvious consequences. The reader can perhaps think of examples, perhaps more than they want to, of bad faith that they have witnessed or taken part in.
Having explained Bad Faith, I will explain how it applies to the contemporary Atheist movement, at least to the cottage industry Atheism that is what most people would be familiar with. The Bad Faith is not only in the specifics of some of the more silly attacks (to take one religious figure who has done bad things, without considering religious figures who have done good things, or Atheists who have done bad things), but in its general philosophical mindset, which is to take a series of propositions, labeled "Natural Science" or (what is so much worse) "Common Sense", and then to not accept that outside of them, there is the Nothingness that defines human possibility, even if it is only cognitive possibility. This comes in large part from the (somewhat simplified) dependence of this strain of Atheism on what could be termed Humean skepticism, or later logical positivism. The world can be treated as a series of mechanical systems, whose rules will eventually be worked out, and everything can be described as part of one of them. Other than the somewhat outmoded truth of this model in physics (it was developed out of Newtonian Physics, which has been proved to be non-complete over a hundred years ago), it of course is a system of Bad Faith. To treat human consciousness as the result of "evolution" is to treat it as in "in-itself", a complete system. The same is true when we speak of any physical system, because even when we have it described perfectly, that is only the "in-itself" of it. To deny that it raises questions and possibilities, that there is a nothingness of doubt and wonder outside of even a completely described physical system, is to be, in my view, in Bad Faith. This Bad Faith to me takes two forms: first, there are technical questions, inherent even in a perfectly described Newtonian physics. The gravitational constant was worked out over two hundred years ago, using equipment no more complicated than metal spheres and tensed wire. And yet, even what that is perfectly known, outside of it is the question "Why is this physical constant this, and not something else?" There are many questions still open in physics and science as to "why" something is the way it is. Even when strictly reduced to things that are considered to be fundamental, we still wonder why a proton is 1836 times as heavy as an electron. But even beyond this, there is a non-technical question: why is there Being instead of Non-Being? Even if we treat the universe as an "in-itself", there is still a mental Nothingness around it, that we must attempt to deal with, even if no answer is possible.
All of this is not to say that Theism is an answer, because there is certainly enough evidence of Theistic systems acting in Bad Faith. And some have tried to do the impossible: to squish the transcendent into yet another "in-itself", to be hauled out when needed to provide social or psychological glue. But to deny that presenting a system, no matter how complete, doesn't answer everyone's questions, is to be in profound Bad Faith. And, of course, I can't get the image out of my mind of Jean-Paul Sartre slowly exhaling tobacco smoke from his nostrils in contempt if he ever heard Richard Dawkins bring Charles Darwin's name up as the conclusive answer to a philosophical question.