Generally speaking, a vampire is a nocturnal creature that drinks human blood. Some are demons, transfigured witches, or natural predatory species, but most are “undead” beings, meaning that they should be dead but remain alive by feeding on the living. Blood-­sucking creatures can be found in myths throughout the world, and in all time periods. Though modern vampire tales tend to have many similarities due to globalization of culture, strikingly similar stories existed in cultures around the globe long before television. The logical conclusion is that the concept of the vampire embodies a fundamental characteristic of the human mind – specifically, fear.

In fact, the development of vampires mirrors Maslow's Hierarchy of Needs. In 1943 Abraham Maslow developed the theory that human needs can be represented as layers of a pyramid. The “physiological” bottom layer – including breathing, food, and water – represents the most elemental, basic needs, and the top layer – self-actualization – includes the most advanced, sophisticated needs.

The oldest vampire legends reveal the most basic fears of humans: being deprived of physiological requirements. After all, little scientific knowledge is needed to realize that losing a large amount of blood will end in death. In addition, vampires illustrate early man's fear of powerful animals. This is why primitive vampire legends described the creatures as inhuman “demons” or shape-shifting beasts. Humans cannot see well in the dark, and are afraid of what dangers lurk therein; hence, most vampires are nocturnal.

But perhaps the trait that made vampiric monsters most terrifying to ancient people was the instinctive fear of death. A vampire is quite literally death come to life, a physical form for an otherwise invisible and unavoidable enemy. By creating monsters, ancient societies gave a body to fears, molding them into killable creatures. What better way to conquer one's deepest fear than to drive a stake through its heart?

As civilizations took shape, humankind reached the second level of Maslow's Hierarchy – the need for a sense of safety – and vampires began to metamorphose. Vampires were already a manifestation of feeling bodily unsafe; in this stage, psychological safety became the concern. One facet of this is the fear of humankind's inner monster. Just as the good-natured man down the street might be thrown into a violent rage under the right circumstances, intermediate vampire legends often emphasized monsters that could appear benign but were in fact terrifying. Consider the Malaysian penanggalan, a female vampire who is an ordinary, if exceptionally beautiful, woman by day, but who transforms herself into a grotesque flying vampire at night.

When vampire literature was born, this second level of fear was the stage of human-vampire evolution that influenced the first horror authors. John Polidori, personal physician to Lord Byron, is credited with the first Gothic vampire novel, The Vampyr. This was the beginning of the modern image of the vampire: a handsome, aristocratic man who is beastly and sadistic like folkloric vampires but also intelligent, personable, and all-too-human at the same time. This Gothic imagining of the monster within would be cemented by Bram Stoker's classic Dracula and Bela Lugosi's cinematic portrayal of that infamous character.

Vampire lore has persisted because of how intimately the myth intertwines with our psyche. As vampires became a reaction to insecurity, people and their legends were already beginning to seep into the realm of complex fears reminiscent of Maslow's third level, the need for affection and acceptance. This was first shown in the connection between vampires and religion. Early mythologies occasionally linked exsanguinating monsters with deities, and then medieval Christianity introduced Judeo-Christian holy objects into European vampire lore. Religion and vampires have been inseparable ever since.

Innumerable vampire movies have featured crosses that send vampires away cowering and hissing. Yet, unless the crucifix doubles as a stake, religious icons would have no power to harm a vampire, so their use relies on first connecting vampires with Satan. To understand how that leap was made, one has to consider the cultural benefits of organized religion.

Religious beliefs are a key solidifier for any civilization, and humans are social animals, needing the companionship of others. Not only are people united by common creeds, but their religion also prevents them from indulging in selfish and violent behavior that could lead to the destruction of the group. For those reasons, religion has been an important part of culture since the beginning, and has mightily influenced monster mythology.

Moral structures, as dictated by religion, are clearly visible in vampiric legend. Folkloric vampires were often created when someone immoral or sacrilegious died. Thus vampire legends served as warnings to would-be sinners. Becoming a hideous walking corpse, damned to eternal restlessness, was considered too great a risk (the idea of vampires having a glamorous afterlife is fairly recent). Furthermore, vampires as religious creatures serve as a tangible reinforcement for an intangible concept. Every time a priest performed a ritual vampire-slaying, villagers were implicitly assured that hellish evil existed in the world. As long as there were monsters, the moral force that kept society functioning remained intact.

In addition, vampires served as an explanation for unexpected deaths. Take for example the proliferation of female vampiric demons believed to be the cause of miscarriages and infant mortalities. Plagues were commonly attributed to the undead before germ theory.

Most modern vampires exist only in popular culture, where they bear little resemblance to the revenants that predated them. Now vampires are sexy – both the holdovers from Gothic tradition and a newer breed of self-pitying “defanged vampires,” in the words of vampirologist Bertena Varney. The defanged vampires in particular – for instance, Edward Cullen from Stephenie Meyer's Twilight – seemed to be designed with romance in mind, not horror.

How did humans come to love what they fear? The answer is likely to be found among those modern vampires that have not been defanged. Spike from the television series “Buffy the Vampire Slayer” remains immensely popular ten years after the last episode aired. Spike has obvious romantic tendencies, as did Dracula and his Gothic brethren, but is equally defined by unapologetic bloodlust and sexual lust. Spike combines the pleasurable and violent aspects of sex as vampire legends have done to some extent for thousands of years. What has allowed the pleasure aspect to overcome the bloody aspect in post-Buffy vampire stories is a changing perception of sex. Civilization has surpassed Maslow's first two tiers of need and in the search for affection has run aground on the shores of Ogygia. A preoccupation with sex has created vampires who exist only for the pleasure of whatever main characters they are paired with. However, fear has not left vampirism entirely. There remains a sense of something dark, primitive, and aggressive lurking in sexual desire. This is perhaps the greatest reason that people find vampires desirable, but also why they still fear them.

Clearly vampire lore has climbed Maslow's pyramid with the human race, but there is a single aspect of fear and vampirism that has not and will never change. “The blood is the life,” and that precious red fluid is as meaningful as ever. I have already discussed the physiological importance of blood, but its symbolic significance is also a component of vampiric terror. If one cannot live without blood, what other powers might the liquid possess? Blood has long been considered a fluid capable of imparting strength and immortality. Modern science has made these ancient sentiments obsolete, but regardless the metaphysical meaning of blood continues to haunt the human mind. In the vampiric relationship, the monster steals blood in order to sustain his or her own supernaturally potent existence; both sides of that coin are frightening to humans because blood is a uniquely symbolic substance.

Every culture has vampires because human beings have certain unalienable fears. In modern times, three gradations of fear have been addressed by the vampire legend as the human race has climbed through three of Maslow's levels of need. The unchanging symbolism of blood, partnered with fears inherent to the human animal, has generated a monster so perfectly suited to the realm of human nightmares that neither time nor distance has been able to dispel it.