#pneumatophysics

Despite numerous scientific advances made in the last few decades, even some of the most fundamental questions about Semblances remain unanswered. Pneumatophysics, along with rhizology (the study of Dust) and archotherology (the study of Grimm), belong to a group of sciences historically known as the Profaned Arts. As recently as three centuries ago, academic inquiries into any of the aforementioned topics were considered stigmatized at best, heretical or blasphemous at worst. All three subjects directly or indirectly pertain to the soul, and thus formed a recurring pancultural trinity throughout Remnant’s past. Pervasive superstition and religious influence often stymied scientific progress, and in some cases this crusade took on more extreme forms, such as destroying physical research, or executing the people that conducted it. While a decreased religiosity led to paradigm shifts in modern culture, the influences of past stigma can still be felt across the four kingdoms where soul research is concerned. In particular, the Kingdom of Atlas, the world’s foremost leader in pneumatophysics, still receives criticism from those who feel that its work sacrifices ethical constraints in favor of “mutilating” the soul.

Estimates on just how many people have discovered their Semblance are notoriously vague. Census data compiled over the last century (starting ca. 2 AB) suggest numbers from as few as 0.25% to 4% (875,000—14,000,000) of the global population, though pneumatophysicists point out that this figure could be substantially lower. Predicting which demographics are most likely to have Semblances is an imprecise measure at best; that being said, Huntsmen, and people living in extraregnal settlements, tend to disproportionately have higher-than-average Semblance discovery rates.

Activation Criteria and Auratic Plasticity

The only prerequisite for discovering one’s Semblance is to have an unlocked Aura. Very seldomly, a person may simultaneously unlock both their Aura and their Semblance, under extreme conditions.

The pathway to unlocking one’s Semblance, while outwardly unpredictable, does seem to be determined by certain factors. Intensive, routine physical activity tends to be the most reliable way to trigger Semblance discovery, although intense emotions have been suggested as another. The type of Semblance a person has, and the circumstances under which it’s gained, are dictated by a mechanism called Auratic plasticity. Auratic plasticity is the ability of the soul to generate a Semblance based on either an individual’s personality (innate), a scenario-specific survival method (adaptive), or a “genetic” trait that’s repeatedly selected for due to its “inherent fitness” (inherited). These three categories are determined by a variable called hierarchical prioritization—the soul’s ability to decide which Semblance-trigger gets precedence.

It’s agreed by the scientific community that there’s an order to Semblance-triggers: inherited > innate > adaptive.

If, for example, a person hailed from a lineage of summoning Semblances, then that person would acquire summoning by default. When a person doesn’t come from a family of inherited Semblances, then they would receive an innate Semblance that aligns with their nature. The last type of Semblance-trigger, adaptive, only occurs when a person is confronted with a life-or-death scenario, and the soul “overrides” the default order to generate a reactionary Semblance tailored to their immediate survival. In the case of an adaptive trigger, a person from a line of summoners could gain an unrelated Semblance, and break the chain.

The discoverer of these mechanisms, Ilere Koya-Hark, famously tested their theory when they went out into a thunderstorm, and induced an electrokinetic Semblance. This experiment laid the groundwork for what would become the field of dilonometry.

It should be noted that any Semblance can be innate, adaptive, or hereditary. There’s no distinction between a hydrokinetic Semblance inherited over generations, or a hydrokinetic Semblance that emerged in response to a near-drowning.

While adaptive and hereditary Semblances are easy enough to understand, innate Semblances are a little trickier. Researchers agree that innate Semblances in some way relate to one’s personality, but it’s debated to what extent—whether a Semblance pertains to a singular, immutable trait, or to one’s overall disposition. And even then, it’s hard to define what, exactly, an innate Semblance says about its user. Does a speed Semblance always mean that a person is hasty? Can it be interpreted as someone who’s limitlessly altruistic, and rushes to others’ aid? Or perhaps it signifies a person that’s energetic and enthusiastic. If innate Semblances can represent multiple traits, then two people with the same Semblance might have drastically different, overall personalities, further muddying the debate.

For now, the consensus is that an innate Semblance is in some way a reflection of one’s soul. Anything more specific than that typically devolves into arguments and fistfights.

Categorization

It’s been disputed just how many Semblances there actually are, and how best to go about divvying them up into neat, consistent headings. At multiple points throughout history, the very idea that Semblances could even be organized into categories was debated, under the belief that “no two Semblances are alike.” This mindset stemmed from a philosophical approach rather than a scientific one, rooted in the idea that souls were so unique as to not be identical, and therefore neither could their Semblances.

Of course, with the benefit of hindsight, that’s not actually the case.

The system currently used for classifying Semblances was devised by Cerise Maida, the archivist of Fort Nubuck, roughly seven decades ago. There are 14 recognized categories each defined by unifying criteria, such as how their powers are expressed, or how they affect the world around them. While far from a perfect system (and not without its criticisms), it’s helped streamline the process for identifying Semblances. More importantly, it allowed apothymeticists to not only clarify what Semblances can do, but what they can’t do.

Absorption Defined as the ability to store physical damage as a form of potential energy, and later release it in a single burst. As the user’s Aura shielding sustains damage, the depletion of their reservoir is “converted” into a latent power that increases over time. This buildup is proportionate to the damage that the user receives. When released, the gathered energy is channeled into a motion—such as a kick or a punch—that drastically amplifies the impact behind the next attack. With enough buildup, a skilled practitioner can deplete an opponent’s Aura in a single hit.

Alteration Defined as the ability to temporarily alter certain qualities of matter, such as temperature, color, tangibility, volume, and opacity. The effects of alteration Semblances can either be self-imposed or directed upon another person or object, once the user initiates contact.

Cloaking Defined as the ability to conceal oneself from the Grimm. There are two varieties of this Semblance: Aura-cloaking and emotion-cloaking. Each has the ability to interfere with a Grimm’s two primary senses (pneumatoception and algeaception), by masking either a person’s Aura signature or their emotional state. Although highly effective against lower-ranking Grimm, the success rate tends to decrease against more dangerous species. Ideally, the Grimm becomes “blind” to the user and cannot distinguish them from ambient sensory data. Under less ideal conditions, a Grimm becomes alerted to the user’s presence but can’t pinpoint their exact location.

Elemental or Kinetic Defined as the ability to generate or manipulate certain expressions of matter/forces. This category contains a diverse range of elemental powers, with common examples including pyrokinesis (fire), hydrokinesis (water), gyrokinesis (gravity), ferrokinesis (metal), electrokinesis (electricity), terrakinesis (earth), and aerokinesis (wind).

Enhancement Defined as the ability to exaggerate or heighten certain physical attributes to an otherwise superhuman level, such as speed, strength, or endurance.

Illusory Defined as the ability to create visual illusions. This power calls false images into existence and projects them into the user’s surroundings. Although these illusions are of a high fidelity, they’re intangible, and lack the mass necessary to be interacted with. With training, the user can increase the complexity or scope of their illusion, and even selectively choose who can or can’t perceive it.

Interference or Modification Defined as the ability to influence another person’s Aura. There are several recognized varieties of this Semblance-type—amplification, bypass, transfer, and suppression—that each directly modifies the target’s Aura when the user touches them. Amplification Semblances allow the user to donate Aura to a recipient from their own reservoir. Bypass Semblances enable the user to disable their target’s Aura shielding. Transfer Semblances allow the user to redistribute Aura between multiple people, by acting as a conduit. Suppression Semblances nullify the target’s Semblance for a brief window of time.

Manifestation Defined as the ability to physically manifest a person’s Aura as extensions of multiple body parts. When activated, the user envelops their limb in an Aura “sheath” that then assumes the function of that body part. From there, the Aura sheath can be manipulated to perform various functions. Examples include forming long, whip-like tendrils that extend from the shoulders, or sharp spines on the soles of one’s feet for traction or increased stability.

Metaphysical Defined as the ability to interfere with the mind. Statistically the rarest Semblances, this heading is often regarded by apothymeticists as a “wastebasket” because of how dissimilar many of the Semblances in this category are from one another. Each interacts with a foreign psyche in some way, be it remote communication (telepathy), temporary episodic wiping (memory repression), or polygraphic intuition (lie detection).

Mimetic Defined as the ability to perfectly mimic body movements and speech patterns observed in others. This Semblance-type is unique in that it doesn’t require the user to have any prior experience in the actions they’re attempting to replicate. A person with no gymnastic training, for example, can still accurately mimic the backflips they once watched someone else perform. This temporary skill acquisition can let the user do things as mundane as copy another person’s handwriting, or imitate an unfamiliar accent.

Probability Defined as the ability to manipulate variables within one’s immediate surroundings to create cause-and-effect changes that either directly benefit the user, or disadvantage others. Also informally known as “luck” Semblances, these are by far the hardest to study in any capacity, given the sometimes-random nature of their effects.

Replication Defined as the ability to create copies, or “shades,” of oneself. Considered one of the more demanding Semblances to master due to its higher Aura requirements, but it’s undeniably powerful to have. The user sacrifices a chunk of their Aura and imparts it upon a copy of themself. Although the copy doesn’t have the ability to use Aura, it does have some considerable bulk and can withstand a specific amount of damage before being destroyed. Copies retain physical mass and are visually identical to their user, making them useful for ganging up on opponents, or deceiving them. Skilled replication users can create an upward number of nine copies; anything beyond that has never been recorded.

Summoning Defined as the ability to conjure apparitions, or thralls, of Grimm that have been defeated before. These spectral creatures share a link with their summoner, and will act in accordance with the user’s will. The user’s proficiency dictates both how many thralls they can summon at once, and what species they’re able to conjure.

Teleportation Defined as the ability to transport a person between locations at will. In order for this Semblance to work, it requires the user to have physically visited the destination at least once before.

Alteration, elemental, replication, and enhancement Semblances are the most commonly-occurring. By contrast, illusory, interference, probability, and metaphysical make up an extremely small percentage of unlocked Semblances.

Active versus Passive Semblances

It’s a generally-accepted fact that Semblances require conscious choice on the part of the user. That being said, there are cases where a person doesn’t always get a say.

The term passive refers to any Semblance that is involuntarily engaged, and runs in the background at a much lesser intensity. Studying them has been notoriously difficult to do, in part due to their rarity and the stigma associated with them. While technically any Semblance can be passive, in theory, certain categories disproportionately represent that number (namely elemental, cloaking, alteration, and probability).

It’s not well understood what causes a Semblance to be passive as opposed to active. One tentative study found a potential correlation, where age and environment were considered factors. A number of study participants who had passive Semblances either unlocked theirs when they were younger (< 9 years old), or as they grew up in unstable home environments. Given the lack of childhood autonomy, it’s been suggested that passive Semblances are formed during adolescence as a coping response to stress.

Just like an active Semblance, a passive Semblance requires Aura in order to function. In exchange for being constantly running, passive Semblances deplete Aura at a significantly decreased rate, and their effects are disproportionately “lesser” than those of active Semblances. With training, a person with a passive Semblance can learn to “direct” it and momentarily bolster its effects.

The impact of a passive Semblance on a person’s quality of life can range from mildly inconvenient to outright debilitating. Some individuals manage by tailoring their daily lives to accommodate their Semblances, whereas others resort to cataspin to keep their Auras (and thus, their Semblances) in a permanently-suppressed state. Doctors typically advise against the latter due to potential negative side effects.

For those reasons, passive Semblances are generally considered a disability.

Limitations

While Semblances can push the boundaries of natural laws, they too are beholden to limitations. Known as Maida’s Four Laws, these limits were described shortly after the establishment of the Semblance category system.

They are defined as such:

A Semblance is restricted to one per person.

A Semblance cannot be used without Aura. If a user’s Aura is inactive, depleted, or suppressed, then the Semblance will fail to work.

A Semblance, once manifested into its current power, cannot change.

A Semblance cannot transfigure a user’s form, or convert matter into a new substance.

Needless to say, these laws have been indispensable to pneumatophysicists in debunking previously-accepted historical accounts. Claims of people transmuting objects into gold were attributed to alteration Semblances, that temporarily made objects gold-colored. Other claims of Semblances turning people into animals were dismissed as folklore.

Similarly, the myth of those with multiple elemental Semblances are now seen as exactly that—a myth.

Regulation and Legal Oversight

Compared to post-war legislation, older laws were far more restrictive.

One such example included the impositions of the Mistrali Empire, which expressly forbade private citizens from unlocking their Aura. Anyone found to have done so—whether accidentally or intentionally—was either forced to enlist (as a guard, ranger, or soldier); was required to pay a monthly tax; or had to take medicine made from Aura-suppressing bellicyclate-rich plants, prescribed by a state-authorized physician.

These measures were meant to serve as deterrents, and discourage anyone from activating their Aura (and by extension, their Semblance). The explanation given under imperial law was to preempt Grimm aggression and encroachment, by reducing the amount of stimuli that their pneumatoception could perceive. It’s been proven that Grimm do, in fact, prioritize targets with unlocked Auras over targets with dormant ones, and that Aura signatures more strongly attract them.

However, historians now accept that the then-given reason was a guise. The Mistrali Empire likely implemented these measures to prevent secessionists from gaining a means to fight back. While anti-Aura and anti-Semblance restrictions weren’t unheard of in other polities, Mistral’s were undisputedly the most authoritarian.

International law passed during the Vytal Summit guarantees considerably more freedoms, regarding one’s Aura. The ability to pursue Semblance-acquisition is considered an inalienable right, and no person may be penalized for doing so. Likewise, Semblance disclosure is considered voluntary (and in many places, is reinforced by cultural taboo). The only demographics legally required to do so are academy students and licensed alumni, who must register their Semblance with their alma mater. Individuals employed in a military or law enforcement role are held to the same standard.

The only time when private citizens are required to disclose the existence of their Semblance is when they’re arrested for criminal charges.

In Non-Humanoid Species

Although all animals have the ability to unlock their Aura, only two species (humans and Faunus) have been observed using Semblances. Researchers in the field of pneumatozoology have suggested that it’s theoretically possible, although it’s not currently known what criteria—if any—is needed to achieve this.

Reception to the idea of animals with Semblances is mixed. Some groups, like Huntsmen, favor the possibility of using a familiar with increased combat aptitude. It’s this same combat aptitude which also garners detractors, who fear that an animal with a Semblance could become a nuisance or a hazard.

Subdisciplines

anthropneumatophysics (Gr. anthro-, an alternative of anthropo-, man, + pneûma, soul, + -physics) A derivation of ethnobiology that deals with the dynamic relationships between humans, Faunus, and Aura. The three underlying topics that researchers focus on concern how people perceive Aura, how people use Aura, and how people react to Aura. Perception addresses Aura from a sociopolitical and cultural standpoint—what beliefs, attitudes, values, and relationships people associate with their Aura on an individual and societal level (be it positive or negative). Usage deals with the various applications of Aura—as a combat tool; as a survival aid; as a sanative accessory; as a Dust catalyst; as an augmentation for industrial labor; as a ceremonial component; and so on. Reaction studies the technological and biological evolution of people and their societies, and in what ways Aura has steered those trajectories over time.

apothymetics (Gr. apo-, derived from, + -thym-, soul, + E. -ics, from [?] Gr. -ikós, pertaining to) The study of Semblances. An argument could be made that apothymetics should itself be further subdivided, to accommodate the wide range of topics that apothymeticists contend with: the categorization of Semblances, the phenomena that determine which type of Semblance is given precedence (Auratic plasticity), the differences between active and passive Semblances, the physical constraints that limit what Semblances can and can’t do, and the adverse effects associated with prolonged or inexperienced Semblance-usage. Ideally, scientists in this discipline would collate their data from a wide range of demographics. Realistically, Huntsmen constitute the majority of their study sample. This is due to [1] Huntsmen disproportionately representing the number of people with unlocked Semblances because of their line of work; and [2] the reluctance of non-Huntsmen to volunteer in academic research.

dilonometry (Gr. dilóno, manifest, + -metry, measurement of) The study of the criteria needed to trigger Aura and Semblance activation. When a person’s Aura is unlocked by another person, it is described as aliquō. When unlocked through non-interventive circumstances, the term per sē is used. The general (albeit tentative and unverified) consensus among scientists is that intense, routine activity predisposes an Aura to spontaneous activation. Similarly, high-stress life-or-death scenarios can cause an Aura to activate (and result in potential simultaneous Semblance acquisition). Research in this field is particularly lucrative, due to a demand for so-called “designer” Semblances that could be artificially generated through manipulating adaptive-selection pathways. Unfortunately, progress in dilonometry is both slow-going and expensive, because the prerequisite for adaptive Semblances (immediate danger) is, needless to say, hard to safely replicate in a controlled setting. A workaround sometimes used by people involves deliberately putting themselves in dangerous scenarios in order to “bait their Aura.”

idiotitology (Gr. idiótita, characteristic, + -logy, study of) The study of inherent characteristics unique to each person’s Aura. Traits such as reservoir capacity (the quantity of Aura each person possesses), chromatic expression (Aura color), and regeneration rate (how quickly a depleted Aura replenishes) can vary wildly between individuals, to the bewilderment of those who study them. It’s not currently understood what factors influence such diversity, or if certain properties (like Aura color) have any significance relative to their commonality. One theory posits that Auratic polymorphism is the result of Grimm selection pressure, although further evidence would be needed to substantiate the evolutionary benefit of Aura color. Another possible theory is that certain Aura characteristics are genetic, or even epigenetic, and may share similar underlying mechanisms with hierarchical prioritization. The final (tentative) theory is that Aura characteristics correlate with an individual’s soul, and convey specific immutable qualities. The latter theory has been difficult to test within an unbiased capacity, given that many cultures associate certain colors with pre-ascribed traits. Without an objective, impartial metric for chromatic expression, it’s impossible to say whether Aura color can be used to identify traits of a person’s soul.

pneumatonosology (Gr. pneûma, soul, + -nosology, study of diseases) The study of Auratic diseases. Given its overlap with archotherology and rhizology, this branch is considered an integrated discipline. Auratic diseases are diagnosed using pathognomonic signs, and then treated with a tailored therapy called electromagnetic field Dust stimulation (EMF-DS therapy). The severity of these conditions ranges from mildly inconvenient, to completely debilitating, to downright lethal, depending on the pathology of the disease and the patient’s overall health. Thankfully, robust medical care ensures either full recovery or improved quality of life for those that become infected. Preventative measures, meanwhile, are somewhat limited to increasing public awareness, as it’s impossible to fully eliminate the vectors of Auratic diseases (plague-type Grimm). The most that epidemiologists can do is monitor their populations, and periodically issue warnings to keep away from areas where sightings have been reported. That being said, there is a subset of Huntsmen who specialize in culling plague-type Grimm, and who are regularly consulted on how to deal with them.