We don't define terms. The terms are already defined. Happiness is an emotion we can experience. Unhappiness is an emotion we can experience. Emotional states are not mutually exclusive; indeed, I'm quite confident that someone who was feeling happy about condition X and unhappy about condition Y at the same time could be physically demonstrated to be exhibiting said emotional states simultaneously via a brain scan.But if we define by the term happy unhappy the same way theist and atheist are herein defined we get that the state of being neither happy or unhappy as being unhappy. That makes sense how?
Whereas, it is not possible for someone to be a theist and an atheist simultaneously. Thus is demonstrated the inherent inapplicability of such an analogy.