Approaching the paranormal from a research perspective is often difficult because of the lack of acceptable physical evidence from most of the purported phenomena. By definition, the paranormal does not conform to conventional expectations of nature. Therefore, a phenomenon cannot be confirmed as paranormal using the scientific method because, if it could be, it would no longer fit the definition. (However, confirmation would result in the phenomenon being reclassified as part of science.) Despite this problem, studies on the paranormal are periodically conducted by researchers from various disciplines. Some researchers simply study the beliefs in the paranormal regardless of whether the phenomena are considered to objectively exist.