I want more than an argument from authority. There is nothing special about psychiatrists that set them apart from the mistakes and fallacies inherit to the human experience, or exempt them from hoax and fraud. What I want is to be careful in my thinking and accepting extraordinary claims with no evidence. I want to be consistent in my logic and conscientious about my observations, so that I may be accurate about my conclusions. You know, the same attitude that has led us to any significant discovery of knowledge ever made.
Atheists have no problem accepting anything but the claim of a deity. We need not depend on atheistic ideas to discount possession, we need only engage in proper investigation and skepticism to see that the claims are completely unsupported. We need only uphold the same standards of evidence and reason we employ in all areas which attempt to provide accurate answers, such as legal, academic and scientific endeavors. We do not need to rely on any religious position, just sophisticated and intelligent inquiry. And let's point out once again, skeptics are willing to accept anything given a convincing and supported argument, you have simply failed to provide one.