When ancient, sacred texts and modern preternatural or paranormal studies are discussed, there is the inevitable implication of reflecting on spiritual entities: Satan, demons, fallen angels, disembodied or deceased individuals (i.e. ghosts or spirits). The ancients took it for granted that these kinds of spiritual entities do exist, whatever and however they sought to deal with them. However, in today's society, it is very suspicious in the minds of many great thinkers, and lay-people alike, that these kinds of spiritual entities exist, and some even resort to prematurely conclude that it is all “fairy-tale.” For an individual who is fully or semi religious, it may fall into the same reasoning as the ancients: that they exist due to personal belief in sacred texts that mention and discuss them, and also due to personal and collective experiences which are, understandably, very subjective. Prior to and until the Protestant Reformations (n.b. there were many reformations, in part, sparked by Martin Luther’s Protestant Reformation), it was the Church that dominated most of society around Europe. After the Protestant reformations, during and after the Age of Enlightenment (i.e. the Age of Reason—in the late 17th century), critical thinkers such as liberal theologians, philosophers, and romanticists began to question outspokenly against the preternatural. Many of these critics began questioning the claims of genuine demon possessions and exorcisms, or the claims for alleged reality of witches, and other sinister characters within the occult—all conjoined with the esoteric beliefs of the time.
This criticism was, for all it’s worth, a healthy reasoning; but a reasoning that, at times, may have gone overboard while overlooking some evidence for the observations and events that claimed genuine paranormal incidents along with their preternatural motifs. Especially from that time on, until our modern age, there have been many fraudulent claims, and ridiculous hoaxes of the preternatural. Truly, once cannot simply rely on hearsay, or individual accounts—unless, of course, an experimenter is one's family member or a close friend. But, on a more credulous and scientific level, individual claims cannot be imported into the established paradigms of science. This is understandably impossible since science (whether empirical or historical) requires not only evidence but coherent interpretation of the alleged evidence. It must also be peer-reviewed and repeatable (if applicable). If it is not repeatable, it should at the least be soundly inferred from available evidence (as in forensics) for the claims to have any acceptable validity by numerous experts who have proven their competence in each field of study. This is all imperative to consider as one can acknowledge and realize all the mistaken assumptions and exposed, false observations made by lay-people and scientists/scholars alike throughout the past centuries. Therefore, it is reasonable for a non-believing, non-religious individual to be suspicious or skeptical about these matters of interest. But, it is equally reasonable for a believing, religious person to undertake the same amount of suspicion and caution. Despite all this, it is absolutely unreasonable to refuse being open-minded, as a lay-person or as a scientist/scholar, and to consciously or unconsciously refuse the possibility of a spiritual sphere of existence in which various entities may truly exist. Now, there is no necessity at this point to mingle and conflate Satan, demons, fallen angels, ghosts, or spirits all into one bag, as if evidence for the existence of one "proves," or evinces the existence of the others.
In summation, the Enlightenment of the late 17th century was a great awakening for the Church and State of the time from all the liberal and scientific reasoning put forth, but it equally shook its foundational claims on religious and cosmological knowledge. Breakthroughs were birthed in science, in theology, in philosophy, in politics, in art, and in education. It also gave rise to what we know today as “peer-review,” and “critical thinking.” Nowadays, the best way one can learn is not simply by reading books, articles, dissertations, and monographs; and by listening to interviews, debates, and lectures on matters of interest (which are all autodidact). But, in addition to all of that, the best learning absorption comes from the interaction with peers and with opponents of one's views. To finalize, it remains to say that sharing this progressive knowledge on these matters deserve respectful insights, suggestions, and corrections by commenters. In the meantime, please have a good laugh at the picture of the skeptical baby (top left).