“Maiste þou not telle me þan,” quod sche, “what þyng is a man?”
“Axest not me,” quod I, “wheþir þat I be a resonable mortel beste? I wot wel, and I confesse wel þat I am it.”
—Geoffrey Chaucer, Boece (c.1378), translating Boethius, De consolatione philosophiae (c.524)

What is a person? The question is always framed in a binary way: is x a person or not? Person or beast? Angel or ape? The question has many practical ramifications, and so it is inevitable that it would get reduced down to this sort of binary decision, because binary on-off states are the easiest way for laws to be written clearly and unambiguously. But just because it is convenient for the law to simplify the situation into a simple binary does not mean that the real underlying situation is binary. To the extent that personhood refers to a real distinction, it must be scalar.

That this is true can be demonstrated by looking at different classes of animals. Higher mammals, such as dolphins, behave far more like established persons than do, say, geckos. And those geckos in turn behave more like persons than do jellyfish. Most species can be assigned to a range on the personhood scale in this manner. Whatever exactly it is that personhood is measuring, with “person” as the supposed perfect state, it is clear that there are scalar differences between different categories of life-form.

Yet there is no reason to think that this spectrum is properly ordinal by species, even if there are significant threshold effects between species, as ordinality is not a phenomenon of nature but of our modelling of nature. There will be jellyfish who exhibit higher degrees of personhood than other jellyfish, geckos who are more person than other geckos, dolphins who are more person than other dolphins. It would be illogical then if this variance was not also observable at the highest end of the scale: that some humans exhibit higher degrees of personhood than other humans. We must ask, not “Is x a person?”, but “How much of a person is x?”. We may still set a threshold above and below which we are happy to refer to “persons”, and this threshold may be variable in different contexts, as we are comfortable with doing for other more obviously scalar words like “tall”. A tall man in ancient Rome would not count as a tall man today; likewise a person in one context may not count as a person in another.

What is personhood?

As in most philosophical problems, there is an ambiguity in how we use the word “person”. Do we mean “person” as it refers to the established persons, all of whom are humans, or do we mean person as it refers to a wider concept of personhood that could be applied beyond humans to other entities we encounter? Traditionally, “(hu)man” and “person” have been used interchangeably, as in Chaucer's passage above. Yet properly these two terms have different types of reference. “Person” is a description of a type of object with certain properties, or at least points to a set of entities, existent and possible, that could be called “persons”. “Human” is a natural kind, referring to a group of entities sharing a particular genetic pattern. There is no necessary reason why those two sets should be coterminous. Not only need we not exclude the possibility of non-human persons, we need not exclude the possibility of non-person humans.

There is similarly an ambiguity in how we use the word “animal”. Here the ambiguity is three-fold. An animal is an organic life-form, composed of DNA and powered by nerves; by this definition, all humans are animals. An animal is also strictly a non-human organic life-form, with the same criteria as above but not human; by this definition, no humans are animals. And an animal is also a non-person, however we end up defining that; by this definition, some humans may be animals (and some non-human life-forms may not be animals). I will use “beast” to mean “non-person”. I will use “animal” to mean roughly “animate organic life-form”, and “non-human animal” to mean roughly “non-human animate organic life-form”.

The traditional view is that what distinguishes humans from non-human animals is that a human is a “rational animal”—the classical “animal rationale” from Aristotle, Chaucer's “reasonable beast”. What is distinctive about this relative to non-person animals is the rationality and the rationality only. That humans also exhibit many irrational behaviours is not a sign that personhood is based instead on unreason: it is a sign that humans are not fully persons. Irrationality does play a key motivating role. Reason itself provides few motives for action. One can hypothesise an intrinsic rational motivation to self-preservation, all else being equal, and that could produce corollary motivations: to eat; to drink; to sleep. But even this imagination does not provide our purely rational being with any motivation to do anything that we consider of higher value, and not even necessarily motive to survive. So it is not to demean the role of the animal nature within humanity to say that it is not a part of personhood.

So the question of “What is personhood?” depends on the question, “What is rationality?”. Rationality is a concept that attempts to describe a real behavioural phenomenon. As such it is both a description of what that behaviour looks like in practice, and a description of what the behaviour ought to look like in theory, and so it can be defined both extensionally, by referring to examples of that behaviour, and intensionally, by describing what would qualify as that behaviour. I assert, from observing persons in action and then describing what an idealised model of their behaviour would be, that rationality has three key threads.

The ability to accurately draw conclusions from premisses.: This ranges from the simplest mathematics to the highest philosophy. It is not only deductive reasoning, but includes of necessity the ability to understand knowledge as probabilistic, and therefore be comfortable with inductive reasoning where it is appropriate. A person need not be, can not be right about everything all of the time: that is inevitable given the probabilistic nature of knowledge. But they must have reached their conclusions carefully, and been willing to change their mind when the evidence changed. This thread is the most fundamental element of rationality, and the other threads build on it.
The ability to assess what is in one's best interests.: This differs from the first because it involves assigning value to outcomes as well as drawing conclusions. It is concrete and practical, applying rationality to the world and maximising one's benefit. Even where other considerations, such as the universal good, over-ride this assessment, a person must have understood what their interest was in order to rationally choose to temporarily ignore it.
The ability to assess what is for the universal good.: This differs from the second because it involves stepping outside oneself to take a universal view. This is the inverse of the hard-nosed second thread, requiring high degrees of abstraction. There is no moral obligation to always follow the universal good, but in choosing to act rationally a person chooses to value rationality. It is consistent to then value rationality to the scalar extent that it exists in others, so a person will tend to act in ways that they consider to be conducive to the greater good. Again, even where other considerations, such as self-interest, over-ride this assessment, a person must have understood what the greater good was.

These three threads entwine together to form the concept of rationality. It is this trinity—reasoning, self-interest, the greater good—that is at the heart of personhood. Yet behaviours are not solely informed by intentions and capacities. In particular in this case, there is a tension between rationality on the one hand, and animalistic passions on the other. Passions (emotions, feelings, sentiments, call them what you will) do not draw from rationality. This does not make them invalid, but it does compromise an individual's personhood. Personhood therefore is not merely the absolute level of an individual's rational capacity, but the exhibition of rationality in their behaviours, which depends on the constantly fluctuating gap between their rationality and their passions.

I do not yet know if this gap is best calculated through subtraction or division, or how much bearing the absolute levels should carry, if any. Imagine that we could measure rationality and passion; after all, we aspire with Galileo to measure what is measurable, and make measurable what is not so. If someone had rationality of 10 and passion of 5, would they be more or less of a person than someone with rationality of 6 and passion of 2? Expressed as a gap, these individuals score 5 and 4; while expressed as division, they score 2 and 3. This fascinating and important question of measurement deserves further thought, and ideally experiment. Tests would need to be devised that could reliably tease out capacity, desire, and behaviour. Current popular theories of behaviour change are too conceptual for this: even where they provide measuring tools, these only measure outcomes contingent on the theory; they are not inputs into the theory itself. This is not a fault per se, and I especially enjoy Ajzen's theories on this in particular, but being able to measure elements as an input to the theory would be an important tool for confirming and sizing the effects.

Consequences

A number of conclusions appear to follow from this philosophical definition of personhood, which may appear obvious to some but are fiercely contested by others and thus worth stating cleanly.

Most normal humans are significantly above any non-human animals that we have observed. Even those animals whose intelligence we admire cannot match the talents of even a human in, say, the 80th percentile, perhaps even lower. As a class, humans truly justify our self-appointed title of "rational animals".
Most humans do not however reach what we might objectively consider to be an especially high standard. Either their rationality is too low to defeat the baseline levels of passion inherent to any animal, or even where they have the capacity for high rationality, they are slaves to their equally florid passions.
There are also some categories of humans who do not meet the standards of philosophical personhood at all. Some unfortunates do not have significant rational capacities at all, never have, and never will. Others either will have greater rational capacities in future, such as children, or had greater rational capacities in the past, such as the elderly or those with brain injuries.
Even where someone does reach a high peak standard of personhood, there will inevitably be times when they slip and allow their emotions to get the better of them. Personhood is not a static condition but a fluctuating one.

These conclusions are important for their practical applications. First, and it is most important to stress this, we can see that our moral intuitions are not aimed at personhood or rationality, but are passions. As such there need be no moral qualms or indignation about withholding the status of philosophical personhood from some groups of humans. Our love and compassion for the severely disabled, as well as for children and the elderly, is not invalidated by their lack of philosophical personhood any more than is our love and compassion for non-human animals.

Second, the significant step difference as a class between humans and non-human animals justifies ascribing legal personhood to all humans, whether or not they qualify as philosophical persons. For purposes of decisions, especially legal ones, scales must of necessity be collapsed to binaries. History suggests that attempting to exclude certain classes of humans from legal personhood is a power too easily exploited by those of ill-intent, who indeed have often themselves been behaving from passion rather than from rationality. The status of human vs non-human is easily measured, and makes a suitable proxy for one useful threshold of personhood.

Third, the necessity of a broad legal threshold for personhood, set at “all humans”, does not require that individuals treat all humans the same, regardless of their philosophical status. Even at a legal level, the classes of absolute non-persons—children, the severely handicapped, and the demented—are not in practice granted all of the active rights that are considered inherent to persons: they cannot vote; they cannot consent; they cannot approve certain legal documents; they may not be able to refuse treatment; etc. This is not considered a moral outrage.

In the same way, we need not worry in our everyday lives about respecting others' plans to equal extent without accounting for their level of personhood. If one wishes to act as though everyone deserves equal respect, fine, but that is a choice, not an obligation. When another individual acts through great passion against our interests or against the universal good, we may act to stop them if we wish, without first stopping to consider if our action is consistent with the rational desire to respect rationality. Their passion has placed them outside the realm of mutual rational respect. Of course, a rational person will often not bother to interfere in another's irrationality because it is of insufficient interest; but the attempt may be made if it is judged appropriate. In many cases the possibility of this will vary with the target's personhood: sometimes they will be persons who ought to be respected, and sometimes not.

Virtues

Finally, we can consider some examples of how a person and a beast would behave in types of circumstance, as a guide for categorising behaviour and as a guide for how to behave if one wishes to be a person. These are only rules of thumb, but may be revealing.

A person is concerned primarily either with the interests of themself and those they directly care for, or with the interests of the whole. A beast is concerned primarily with the interests of the tribe with which they passionately identify, and for which they experience passionate social pressure to feel passion.
A person tries to consider all sides of an issue; it may be that an extreme end of a scale is most meritorious, but the whole scale will have been considered. A beast picks a single position and defends it regardless of its merits, because it is the beast's position (or often, the position of its tribe).
A person assesses all values either from their own position, which has practical merit, or from the universal position, which has rational merit, and does not have loyalty where that means allegiance regardless of merit. A beast assesses values from the position of their “side”, and is loyal regardless of merit.
A person recognises that the world is scalar and finite, and that therefore all decisions are trade-offs between competing goods. A beast treats everything as an absolute and refuses to consider compromise.
A person recognises that knowledge is probabilistic, and that therefore others behaving rationally might be right, or at least might have a valid case for assigning different probabilities to knowledge. A beast tends to ascribe malice to others who disagree, or if feeling very generous, gross stupidity.
A person, valuing the universal good, makes efforts to experience dissenting views and understand alien viewpoints, even if only to understand why they are likely to be wrong. A beast remains within the tribe, reinforcing the hold the tribe's passions have on them.
A person values quality, and will not reject something good because of a malicious provenance. A beast values the passion of suffering, considering it an evil in inflicting on others, and a virtue in having it inflicted on oneself.

sum θoətiz abaʊt puəsəniz and biistiz

“Maiste þou not telle me þan,” quod sche, “what þyng is a man?” “Axest not me,” quod I, “wheþir þat I be a resonable mortel beste? I wot wel, and I confesse wel þat I am it.”
“kwes ðii mei tel not mii,” hii seiyid, “wot ðiŋ biiy a man?” “kwes ðiiy ask not mii,” mii seiyid, “weðə mii biiy a riizənəbəl mʊətəl biist? mii noʊ wel, and mii kənfes wel ðat mii bii ðat.”
—jefrii cʊəsə, boʊwiis (s.1378), tranzleitiŋ boʊwiiθiiyəs, dei konsolatiiyoʊnei filosofiiyei (s.524)

kwes wot biiy a puəsən? ðə kwescən bii oəlweiz freiməð in a bainərii wei: kwes bii x a puəsən oə not? puəsən oə biist? einjəl oər eip? ðə kwescən hav menii praktikəl ramifikeiʃəniz, and soʊ hii bii inevitəbəl ðat hii wʊd get rejʊʊsəð daʊn tə ðis soət ov bainərii disiʒən, bikuz bainəriiy on-of steitiz bii ðiiy iiziiyist wei foə loəriz tə bii raitəð kliəliiy and unambigyʊʊwəslii. but just bikuz hii bii kənviiniiyənt foə ðə loə tə simplifai ðə sicʊʊweiʃən intʊʊw a simpəl bainərii miin not ðat ðə riil undəlaiyiŋ sicʊʊweiʃən bii bainərii. tə ðiiy ekstent ðat puəsənhʊd rifuər tʊʊw a riil distinkʃən, hii must bii skeilə.

ðat ðis bii trʊʊ kan bii demənstreitəð bai lʊkiŋg at difrənt klasiz ov animəliz. haiyə maməliz, suc az dolfiniz, biheiv faə mʊə laik establiʃəð puəsəniz ðan dʊʊ, sei, gekoʊwiz. and ðoʊz gekoʊwiz in tuən biheiv mʊə laik puəsəniz ðan dʊʊ jeliifiʃ. moʊst spiiʃiiziz kan biiy asainəð tʊʊw a reinj on ðə puəsənhʊd skeil in ðis manə. wotevər egzaktlii hii bii ðat puəsənhʊd bii meʒərin, wið “puəsən” az ðə supoʊzəð puəfekt steit, hii bii kliə ðat ðeə bii skeilə difrənsiz bitwiin difrənt katəgriiyiz ov laif-fʊəm.

yet ðeə bii noʊ riizən tə θink ðat ðis spektrəm bii propəliiy ʊədinəl bai spiiʃiiz, iivən if ðeə bii signifikənt θreʃhoʊld efektiz bitwiin spiiʃiiziz, az ʊədinalitii bii not a fenomənon ov neicə but ov wiis modəliŋg ov neicə. ðeə biiyil jeliifiʃ hʊʊw egzibit haiyə digriiyiz ov puəsənhʊd ðan uðə jeliifiʃ, gekoʊwiz hʊʊ bii mʊə puəsən ðan uðə gekoʊwiz, dolfiniz hʊʊ bii mʊə puəsən ðan uðə dolfiniz. hii wʊd biiy ilojikəl ðen if ðis veəriiyəns biiyid not oəlsoʊw obzuəvəbəl at ðə haiyist end ov ðə skeil: ðat sum hyʊʊuməniz egzibit haiyə digriiyiz ov puəsənhʊd ðan uðə hyʊʊməniz. wii must ask, not “kwes bii x a puəsən?”, but “kwes haʊ muc ov a puəsən bii x?”. wii mei stil set a θreʃhoʊld abuv and biloʊ wic wii bii hapii tə rifuə tə “puəsəniz”, and ðis θreʃhoʊld mei bii veəriiyəbəl in difrənt kontekstiz, az wii bii kəmfətəbəl wið dʊʊwiin foər uðə mʊər obviiyəslii skeilə wuədiz laik “toəl”. a toəl man in einʃənt roʊm wʊd not kaʊnt az a toəl man tədei; laikwaiz a puəsən in um kontekst mei not kaʊnt az a puəsən in anuðə.

kwes wot bii puəsənhʊd?

az in moʊst filəsofikəl probləmiz, ðeə biiy an ambigyʊʊwitiiy in haʊ wii yʊʊz ðə wuəd “puəsən”. kwes wii miin “puəsən” az hii rifuə tə ðiiy istabliʃəð puəsəniz, oəl ov hʊʊ bii hyʊʊməniz, oə kwes wii miin puəsən az hii rifuə tʊʊw a waidə konsept ov puəsənhʊd ðat kʊd biiy aplaiyəð biiyond hyʊʊməniz tʊʊw uðər entitiiyiz wiiy inkaʊntə? tradiʃənəlii, “(hyʊʊ)man” and “puəsən” biiyiv yʊʊzəð intəceinjəbliiy, az in cʊəsər-iis pasij abuv. yet propəlii ðiiz tʊʊ tuəmiz hav difrənt taipiz ov refrəns. “puəsən” biiy a diskripʃən ov a taip ov objekt wið suətən propətiiyiz, oər at liist point tʊʊw a set ov entitiiyiz, egzistənt and posibəl, ðat kʊd bii koələð “puəsəniz”. “hyʊʊmən” biiy a nacərəl kaind, rifuəriŋ tʊʊw a grʊʊp ov entitiiyiz ʃeəriŋg a pətikyələ jinetik patən. ðeə bii noʊ nesiserii riizən wai ðoʊz tʊʊ setiz ʃʊd bii koʊtuəminəs. not oʊnlii niid wii not eksklʊʊd ðə posibilitiiy ov non-hyʊʊmən puəsəniz, wii niid not eksklʊʊd ðə posibilitiiy ov non-puəsən hyʊʊməniz.

ðeə bii similəliiy an ambigyʊʊwitiiy in haʊ wii yʊʊz ðə wuəd “animəl”. hiə ðiiy ambigyʊʊwitii bii tii-foʊld. an animəl biiy an ʊəganik laif-fʊəm, kəmpoʊzəð ov dna and paʊwərəð bai nuəviz; bai ðis definiʃən, oəl hyʊʊməniz biiy animəliz. an animəl biiy oəlsoʊ striktliiy a non-hyʊʊmən ʊəganik laif-fʊəm, wið ðə seim kraitiəriiyər az abuv but not hyʊʊmən; bai ðis definiʃən, noʊ hyʊʊməniz biiy animəliz. and an animəl biiy oəlsoʊw a non-puəsən, haʊwevə wiiy end up difainiŋ ðat; bai ðis definiʃən, sum hyʊʊməniz mei biiy animəliz (and sum non-hyʊʊmən laif-fʊəmiz mei not biiy animəliz). mii yʊʊzil “biist” tə miin “non-puəsən”. mii yʊʊzil “animəl” tə miin rufliiy “animət ʊəganik laif-fʊəm”, and “non-hyʊʊmən animəl” tə miin ruflii “non-hyʊʊmən animət ʊəganik laif-fʊəm”.

ðə tradiʃənəl vyʊʊ bii ðat wot distingwiʃ hyʊʊməniz from non-hyʊʊmən animəliz bii ðat a hyʊʊmən biiy a “raʃənəl animəl”—ðə klasikəl “animəl raʃənaəlei” from aristotəl, cʊəsər-iis “riizənəbəl bist”. wot bii distinktiv abaʊt ðis relətiv tə non-puəsən animəliz bii ðə raʃənalitiiy and ðə raʃənalitiiy oʊnlii. ðat hyʊʊməniz oəlsoʊw egzibit meniiy iraʃənəl biheiviiyəriz bii not a sain ðat puəsənhʊd bii beisəð insted on unriizən: hii biiy a sain ðat hyʊʊməniz bii not fʊlii puəsəniz. iraʃənalitii dʊʊ pleiy a kii moʊtiveitiŋ roʊl. riizən hiiself prəvaid fyʊʊ moʊtiviz foər akʃən. um kan haipoθəsaiz an intrinsik raʃənəl moʊtiveiʃən tə self-prezəveiʃən, oəl els biiyiŋg iiqwəl, and ðat kʊd prəjʊʊs korolərii moʊtiveiʃəniz: tʊʊw iit; tə drink; tə sliip. but iivən ðis imajineiʃən prəvaid not wiis pyʊəlii raʃənəl biiyiŋ wið enii moʊtiveiʃən tə dʊʊw eniiθiŋ ðat wii kənsidər ov haiyə valyʊʊ, and not iivən neseserilii moʊtiv tə səvaiv. soʊ hii bii not tə dimiin ðə roʊl ov ðiiy animəl neicə wiðin hyʊʊmanitii tə sei ðat hii bii not a paət ov puəsənhʊd.

soʊ ðə kwescən ov “kwes wot bii puəsənhʊd?” dipend on ðə kwescən, “kwes wot bii raʃənalitii?”. raʃənalitii biiy a konsept ðat atemt tə diskraib a riil biheivyərəl fənomenon. az suc hii bii boʊθ a diskripʃən ov wot ðat biheivyə lʊk laik in praktis, and a diskripʃən ov wot ðə biheivyər ʊət tə lʊk laik in θiəriiy, and soʊ hii kan bii difainəð boʊθ ekstenʃənəlii, bai rifuəriŋ tʊʊw egzampəliz ov ðat biheivyər, and intenʃənəlii, bai diskraibiŋg wot wʊd kwolifaiy az ðat biheivyə. miiy asuət, from obzuəviŋ puəsəniz in akʃən and ðen diskraibiŋg wot an aidiiyəlaizəð modəl ov diis biheivyə wʊd bii, ðat raʃənalitii hav tii kii θrediz.

ðiiy abilitii tʊʊw akyərətlii droə kənklʊʊʒəniz from premisiz.: ðis reinj from ðə simplist maθimatiks tə ðə haiyist filosəfii. ðat bii not oʊnlii diduktiv riizəniŋ, but inklʊʊd ov nisesitii ðiiy abilitii tʊʊw undəstand nolij az probəbəlistik, and ðeəfoə bii kumftəbəl wið induktiv riizəniŋg weə it biiy aproʊpriiyət. a puəsən niid not bii, kan not bii rait abaʊt evriθiŋg oəl ov ðə taim: ðat biiy inevitəbəl givəð ðə probəbəlistik neicər ov nolij. but dii must riiciv diis kənklʊʊʒəniz keəfəlii, and biiyiv wiliŋ tə ceinj diis maind wen ðiiy evidəns ceinjid. ðis θred bii ðə moʊst fundəmentəl elemənt ov raʃənalitiiy, and ðiiy uðə θrediz bild on hii.
ðiiy abilitii tʊʊw ases wot biiy in um-iis best intrestiz.: ðis difə from ðə umθ bikuz hii involv asainiŋ valyʊʊ tʊʊw aʊtkəmiz az wel az droəriŋ kənklʊʊʒəniz. hii bii konkriit and praktikəl, aplaiyin raʃənalitii tə ðə wuəld and maksimaizin um-iis benifit. iivən weər uðə kənsidəreiʃəniz, suc az ðə yʊʊnivuəsəl gʊd, oʊvə-raid ðis asesmənt, a puəsən must undəstandiv wot diis intrest biiyid in ʊədə tə raʃənəlii cʊʊz tə tempəreəriliiy ignʊə hii.
ðiiy abilitii tʊʊw ases wot bii foə ðə yʊʊnivuəsəl gʊd.: ðis difə from ðə tʊʊθ bikuz hii involv stepiŋg aʊtsaid umself tə teik a yʊʊnivuəsəl vyʊʊ. ðis bii ðiiy invuəs ov ðə haəd-noʊzəð tʊʊθ θred, rikwaiəriŋg hai digriiyiz ov abstrakʃən. ðeə bii noʊ morəl obligeiʃən tʊʊw oəlweiz foloʊ ðə yʊʊnivuəsəl gʊd, but in cʊʊziŋ tʊʊw akt raʃənəliiy a puəsən cʊʊz tə valyʊʊ raʃənalitii. ðat bii kənsistənt tə ðen valyʊʊ raʃənalitii tə ðə skeilə ekstent ðat hiiy egzist in uəriz, soʊw a puəsən tendil tʊʊw akt in weiyiz ðat hii kənsidə tə bii kəndyʊʊsiv tə ðə greitə gʊd. agen, iivən weər uðə kənsidəreiʃəniz, suc az self-intrest, oʊvə-raid ðis asesmənt, a puəsən must undəstandiv wot ðə greitə gʊd biiyid.

ðiiz tii θrediz entwain təgeðə tə fʊəm ðə konsept ov raʃənalitii. ðis trinitii—riizəniŋ, self-intrest, ðə greitə gʊd—biiy at ðə haət ov puəsənhʊd. yet biheivyəriz bii not soʊl-lii infʊəməð baiy intenʃəniz and kapasitiiyiz. in pətikyələ in ðis keis, ðeə biiy a tenʃən bitwiin raʃənalitiiy on ðiiy um hand, and animəlistik paʃəniz on ðiiy uðə. paʃəniz (imoʊʃəniz, fiiliŋgiz, sentiməntiz, koəl dii wot yii wil) droə not from raʃənalitii. ðis meik not diiy invalid, but ðis dʊʊw komprəmaiz an indivijʊʊwəl's puəsənhʊd. puəsənhʊd ðeəfoə bii not miəlii ðiiy absəlʊʊt levəl ov an indivijʊʊwəl-iis raʃənəl kapasitii, but ðiiy eksibiʃən ov raʃənalitiiy in hiis biheivyəriz, wic dipend on ðə konstəntlii flukcʊʊweitiŋ gap bitwiin hiis raʃənalitiiy and hiis paʃəniz.

mii yet noʊ not if ðis gap bii best kalkəleitəð θrʊʊ subtrakʃən oə diviʒən, oə haʊ muc beəriŋ ðiiy absəlʊʊt levəliz ʃʊd kariiy, if eniiy. imagən ðat wii kʊd meʒə raʃənalitiiy and paʃən; aftər oəl, wiiy aspaiə wið galileiyoʊ tə meʒə wot bii meʒərəbəl, and meik meʒərəbəl wot bii not soʊ. if sum-um havid raʃənalitiiy ov dein and paʃən ov fi, wʊd hii bii mʊər oə les ov a puəsən ðan sum-um wið raʃənalitiiy ov so and paʃən ov tʊʊw? ekspressəð az a gap, ðiiz indivijʊʊwəliz skʊə fih and fo; wail ekspresəð az diviʒən, dii skʊə tʊʊw and tii. ðis fasineitiŋg and impʊətənt kwescən ov meʒəmənt dizuəv fuəðə θoət, and idiiəliiy eksperimənt. testiz wʊd niid tə bii divaizəð ðat kʊd rilaiyəblii tiiz aʊt kapasitii, dizaiər, and biheivyə. kurənt popyələ θiəriiyiz ov biheivyə ceinj bii tʊʊ kənsepcʊʊwəl foə ðis: iivən weə dii prəvaid meʒəriŋ tʊʊliz, ðiiz oʊnlii meʒə aʊt-kumiz kəntinjənt on ðə θiərii; dii bii not inpʊtiz intʊʊ ðə θiəriiy hiiself. ðis bii not a folt puə seiy, and mii espeʃəliiy injoiy ajzən-iis θiəriiyiz on ðis in pətikyələ, but biiyiŋg eibəl tə meʒər eləməntiz az an inpʊt tə ðə θiərii wʊd biiy an impʊətənt tʊʊl foə kənfuərmiŋg and saiziŋ ðiiy efektiz.

konsikqensiz

a numbər ov kənklʊʊʒəniz apiə tə foloʊ from ðis filəsofikəl definiʃən ov puəsənhʊd, wic meiy apiər obviiyəs tə sum but bii fiəslii kəntestəð baiy uðəriz and ðus wuəθ steitiŋ kliinlii.

moʊst noəməl hyʊʊməniz bii signifikəntliiy abuv enii non-hyʊʊmən animəliz ðat wii obzuəviv. iivən ðoʊz animəliz hʊʊwiis intelijəns wiiy admaiə kan not mac ðə taləntiz ov iivən a hyʊʊmən in, sei, ðə nuə-deinth pəsentail, pəhaps iivən loʊwə. az a klas, hyʊʊməniz trʊʊlii justifai wiis self-apointəð taitəl ov "raʃənəl animəliz".
moʊst hyʊʊməniz haʊw-evə riic not wot wii mait objektivlii kənsidə tə biiy an espeʃəlii hai standəd. iiðə diis raʃənalitii bii tʊʊ loʊ tə difiit ðə beis-lain levəliz ov paʃən inherənt tʊʊw eniiy animəl, oər iivən weə dii hav ðə kapasitii foə hai raʃənalitii, dii bii sleiviz tə diis iikwəlii florid paʃəniz.
ðeə biiy oəlsoʊ sum katigəriiyiz ov hyʊʊməniz hʊʊ miit not ðə standədiz ov filəsofikəl puəsənhʊd at oəl. sum unfʊəcənətiz hav not signifikənt raʃənəl kapasitiiyiz at oəl, nevə havid, and nevə havil. uðəriz aiðə havil greitə raʃənəl kapasitiiyiz in fyʊʊcə, suc az cildrən, oə havid greitə raʃənəl kapasitiiyiz in ðə past, suc az ðiiy eldəliiy oə ðoʊz wið brein injəriiyiz.
iivən weə sum-um dʊʊ riic a hai piik standəd ov puəsənhʊd, ðeər inevitəblii biiyil taimiz wen hii slip and alaʊ hiis imoʊʃəniz tə get ðə betər ov hii. puəsənhʊd bii not a statik kondiʃən but a flukcʊʊweitiŋg um.

ðiiz kənklʊʊʒəniz biiy impʊətənt foə diis praktikəl aplikeiʃəniz. umθ, and ðis bii moʊst impʊətənt tə stres ðis, wii kan sii ðat wiis morəl incʊʊwiʃəniz bii not eiməð at puəsənhʊd oə raʃənalitii, but bii paʃəniz. az suc ðeə niid bii noʊ morəl kwaəmiz oər indigneiʃən abaʊt wið-hoʊldiŋ ðə steitəs ov filəsofikəl puəsənhʊd from sum grʊʊpiz ov hyʊʊməniz. wiis luv and kəmpaʃən foə ðə siviəlii diseibələð, az wel az foə cildrən and ðiiy eldəlii, bii not invalideitəð bai diis lak ov filəsofikəl puəsənhʊd enii mʊə ðan bii wiis luv and kəmpaʃən foə non-hyʊʊmən animəliz.

tʊʊθ, ðə signifikənt step difrəns az a klas bitwiin hyʊʊməniz and non-hyʊʊmən animəliz justifaiy askraibiŋg liigəl puəsənhʊd tʊʊw oəl hyʊʊməniz, weðər oə not dii kwolifaiy az filəsofikəl puəsəniz. foə puəpəsiz ov disiʒəniz, espeʃəlii liigəl umiz, skeiliz must ov nesesitii bii kəlapsəð tə bainəriiyiz. histərii sujest ðat atemptiŋ tʊʊw eksklʊʊd suətən klasiz ov hyʊʊməniz from liigəl puəsənhʊd biiy a paʊwə tʊʊw iiziliiy eksploitəð bai ðoʊz ov il-intent, hʊʊw indiid biiyiv oftən dii-selfiz biheiviŋ from paʃən raəðə ðan from raʃənalitii. ðə steitəs ov hyʊʊmən vs non-hyʊʊmən biiy iizilii meʒərəð, and meik a sʊʊtəbəl proksii foər um yʊʊsfəl θreʃoʊld ov puəsənhʊd.

tiiθ, ðə nesesitiiy ov a broəd liigəl θreʃoʊld foə puəsənhʊd, set at “oəl hyʊʊməniz”, rikwaiə not ðat indivijʊʊwəliz triit oəl hyʊʊməniz ðə seim, rigaədləs ov diis filəsofikəl steitəs. iivən at a liigəl levəl, ðə klasiz ov absəlʊʊt non-puəsəniz—cildrən, ðə siviəlii handikapəð, and ðə dimentəð—bii not in praktis grantəð oəl ov ðiiy aktiv raitiz ðat bii kənsidərəð inherənt tə puəsəniz: dii kan not voʊt; dii kan not kənsent; dii kan not aprʊʊv suətən liigəl dokyəməntiz; dii mei not biiy eibəl tə rifyʊʊz triitmənt; ets. ðis bii not kənsidərəð a morəl aʊtreij.

in ðə seim wei, wii niid not wuriiy in wiis evrii-dei laifiz abaʊt rispektiŋg uðər-iis planiz tʊʊw iikwəl ekstent wiðaʊt akaʊntiŋ foə diis levəl ov puəsənhʊd. if um wiʃ tʊʊw akt az ðoʊw evriiy-um dizuəv iikwəl rispekt, fain, but ðat biiy a cois, not an obligeiʃən. wen anuðər indivijʊʊwəl akt θrʊʊ greit paʃən agenst wiis intrestiz oər agenst ðə yʊʊnivuəsəl gʊd, wii meiy akt tə stop hii if wii wiʃ, wiðaʊt umθ stopiŋ tə kənsidər if wiis akʃən bii kənsistənt wið ðə raʃənəl dizaiə tə rispekt raʃənalitii. hiis paʃən pleisiv hii aʊt-said ðə relm ov myʊʊcʊʊwəl raʃənəl rispekt. ov koəs, a raʃənəl puəsən oftən boðəril not tʊʊw intəfiər in anuðər-iis iraʃnalitii bikuz ðat biiy ov insufiʃənt intrest; but ðiiy atemt mei bii meikəð if ðat bii jujəð aproʊpriiyət. in menii keisiz ðə posibilitiiy ov ðis veiriiyil wið ðə taəgit-iis puəsənhʊd: sum-taimiz dii biiyil puəsəniz hʊʊw ʊət tə bii rispektəð, and sum-taimiz not.

vuəcʊʊwiz

fainəlii, wii kan kənsidə sum egzampəliz ov haʊw a puəsən and a biist wʊd biheiv in taipiz ov suəkəmstans, az a gaid foə kategəraiziŋ biheivyər and az a gaid foə haʊ tə biheiv if um wiʃ tə biiy a puəsən. ðiiz biiy oʊnlii rʊʊliz ov θum, but mei bii riviiliŋ.

a puəsən bii kənsuənəð praimeriliiʸ aiðə wið ðiiʸ intrestiz ov diiself and ðoʊz dii dairektlii keə foəʳ, oə wið ðiiʸ intrestiz ov ðə hoʊl. a biist bii kənsuənəð praimerilii wið ðiiʸ intrestiz ov ðə traib wið wic dii paʃənətliiʸ aidentifaiʸ, and foə wic diiʸ ekspiəriiəns paʃənət soʊʃəl preʃə tə fiil paʃən.
a puəsən trai tə kənsidər oəl saidiz ov an iʃʊʊ; ðat mei bii ðat an ekstriim end ov a skeil bii moʊst meritʊəriiyəs, but ðə hoʊl skeil biiyivil kənsidərəð. a biist pik a singəl pəziʃən and difend hii rigaədləs ov hiis meritiz, bikuz hii bii ðə biist-iis pəziʃən (oər oftən, ðə pəziʃən ov hiis traib).
a puəsən ases oəl valyʊʊwiz aiðə from hiis oʊn pəziʃən, wic hav praktikəl merit, oə from ðə yʊʊnivuəsəl pəziʃən, wic hav raʃənəl merit, and hav not loiyəltii weə ðat miin aliijəns rigaədləs ov merit. a biist ases valyʊʊwiz from ðə pəziʃən ov hiis “said”, and bii loiyəl rigaədləs ov merit.
a puəsən rekəgnaiz ðat ðə wuəld bii skeilər and fainait, and ðat ðeəfoər oəl disiʒəniz bii treid-ofiz bitwiin kəmpiitiŋ gʊdiz. a biist triit evriθiŋg az an absəlʊʊt and rifyʊʊz tə kənsidə komprəmaiz.
a puəsən rekəgnaiz ðat nolij nii probəblistik, and ðat ðeəfoər uðəriz biheiviŋg raʃənəlii mait bii rait, oər at liist mait hav a valid keis foər asainiŋ difrənt probəbilitiiyiz tə nolij. a biist tend tʊʊw askraib malis tʊʊw uðəriz hʊʊ disəgriiy, oər if fiiliŋ verii jenərəs, groʊs styʊʊpiditii.
a puəsən, valyʊʊwiŋ ðə yʊʊnivuəsəl gʊd, meik efətiz tʊʊw ekspiəriiyəns disentiŋ vyʊʊwiz and undəstand eilyən vyʊʊ-pointiz, iivən if oʊnlii tʊʊw undəstand wai dii bii laiklii tə bii roŋg. a biist rimein wiðin ðə traib, riiyinfʊəsiŋ ðə hoʊld ðə traib-iis paʃəniz hav on hii.
a puəsən valyʊʊ kwolitiiy, and rijektil not sum-θiŋ gʊd bikuz ov a maliʃəs provenəns. a biist valyʊʊ ðə paʃən ov sufəriŋ, kənsidəriŋ ðat an iivil in infliktiŋg on uðəriz, and a vuəcʊʊw in haviŋ suc infliktəð on um-self.