|a dead relative|
A person is a being, such as a human, that has certain capacities or attributes constituting personhood, which in turn is defined differently by different authors in different disciplines, and by different cultures in different times and places. In ancient Rome, the word "persona" (Latin) or "prosopon" (πρόσωπον: Greek) originally referred to the masks worn by actors on stage. The various masks represented the various "personae" in the stage play.
The current concept of person was developed during the Trinitarian and Christological debates of the 4th and 5th centuries in contrast to the word nature. During the theological debates, some'philosophical tools (concepts) were needed so that the debates could be held on common basis to all theological schools. The purpose of the debate was to establish the relation, similarities and differences between the Λóγος/"Verbum" and God. The philosophical concept of person arose, taking the word "prosopon" (πρόσωπον) from the Greek theatre. Therefore, Christus (the Λóγος/"Verbum") and God were defined as different "persons". This concept was applied later to the Holy Ghost, the angels and to all human beings.
personal identity: both about what makes any particular person that particular person instead of another, and about what makes a person at one time the same person as he or she was or will be at another time despite any intervening changes. The common plural of "person", "people", is often used to refer to an entire nation or ethnic group (as in "a people"). The plural "persons" is often used in philosophical and legal writing.
Western Philosophy[edit source]
In philosophy, the word "person" may refer to various concepts. According to the "naturalist" epistemological tradition, from Descartes through Locke and Hume, the term may designate any human (or non-human) agent which: (1) possesses continuous consciousness over time; and (2) who is therefore capable of framing representations about the world, formulating plans and acting on them.
According to Charles Taylor, the problem with the naturalist view is that it depends solely on a "performance criterion" to determine what is an agent. Thus, other things (e.g. machines or animals) that exhibit "similarly complex adaptive behaviour" could not be distinguished from persons. Instead, Taylor proposes a significance-based view of personhood:
What is crucial about agents is that things matter to them. We thus cannot simply identify agents by a performance criterion, nor assimilate animals to machines... [likewise] there are matters of significance for human beings which are peculiarly human, and have no analogue with animals.—
Others, such as American Philosopher Francis J. Beckwith, argue that personhood is not linked to function at all, but rather that it is the underlying personal unity of the individual.
What is crucial morally is the being of a person, not his or her functioning. A human person does not come into existence when human function arises, but rather, a human person is an entity who has the natural inherent capacity to give rise to human functions, whether or not those functions are ever attained. …A human person who lacks the ability to think rationally (either because she is too young or she suffers from a disability) is still a human person because of her nature. Consequently, it makes sense to speak of a human being’s lack if and only if she is an actual person.—
Philosopher J. P. Moreland clarifies this point:
It is because an entity has an essence and falls within a natural kind that it can possess a unity of dispositions, capacities, parts and properties at a given time and can maintain identity through change.—
Harry G. Frankfurt writes that, "What philosophers have lately come to accept as analysis of the concept of a person is not actually analysis of that concept at all." He suggests that the concept of a person is intimately connected to free will, and describes the structure of human volitionaccording to first- and second-order desires:
Besides wanting and choosing and being moved to do this or that, [humans] may also want to have (or not to have) certain desires and motives. They are capable of wanting to be different, in their preferences and purposes, from what they are. Many animals appear to have the capacity for what I shall call "first-order desires" or "desires of the first order," which are simply desires to do or not to do one thing or another. No animal other than man, however, appears to have the capacity for reflective self-evaluation that is manifested in the formation of second-order desires.—
The criteria for being a person... are designed to capture those attributes which are the subject of our most humane concern with ourselves and the source of what we regard as most important and most problematical in our lives.—Harry G. Frankfurt
According to Nikolas Kompridis, there might also be an intersubjective, or interpersonal, basis to personhood:
What if personal identity is constituted in, and sustained through, our relations with others, such that were we to erase our relations with our significant others we would also erase the conditions of our self-intelligibility? As it turns out, this erasure... is precisely what is experimentally dramatized in the “science fiction” film, Eternal Sunshine of the Spotless Mind, a far more philosophically sophisticated meditation on personal identity than is found in most of the contemporary literature on the topic.—
Other philosophers have defined persons in different ways. Boethius gives the definition of "person" as "an individual substance of a rational nature" ("Naturæ rationalis individua substantia"). Peter Singer defines a “person” as being a conscious, thinking being, which knows that it is a person (self-awareness).
Philosopher Thomas I. White argues that the criteria for a person are as follows: (1) is alive, (2) is aware, (3) feels positive and negative sensations, (4) has emotions, (5) has a sense of self, (6) controls its own behaviour, (7) recognises other persons and treats them appropriately, and (8) has a variety of sophisticated cognitive abilities. While many of White's criteria are somewhat anthropocentric, some animals such as dolphins would still be considered persons. Some animal rights groups have also championed recognition for animals as "persons".
Another approach to personhood, Paradigm Case Formulation, used in Descriptive Psychology and developed by Peter Ossorio, involves the four interrelated concepts of 1) The Individual Person, 2) Deliberate Action, 3) Reality and the Real World, and 4) Language or Verbal Behavior. All four concepts require full articulation for any one of them to be fully intelligible. More specifically, a Person is an individual whose history is, paradigmatically, a history of Deliberate Action in a Dramaturgical pattern. Deliberate Action is a form of behavior in which a person (a) engages in an Intentional Action, (b) is cognizant of that, and (c) has chosen to do that. A person is not always engaged in a deliberate action but has the eligibility to do so. A human being is an individual who is both a person and a specimen of Homo sapiens. Since persons are deliberate actors, they also employ hedonic, prudent, aesthetic and ethical reasons when selecting, choosing or deciding on a course of action. As part of our "social contract" we expect that the normal person can make use of all four of these motivational perspectives. Individual persons will weigh these motives in a manner that reflects their personal characteristics. That life is lived in a “dramaturgical” pattern is to say that people make sense, that their lives have patterns of significance. The paradigm case allows for nonhuman persons, potential persons, nascent persons, manufactured persons, former persons, "deficit case" persons, and "primitive" persons. By using a paradigm case methodology, different observers can point to where they agree and where they disagree about whether an entity qualifies as a person.  
American Law[edit source]
A person is recognized by law as such, not because he is human, but because rights and duties are ascribed to him. The person is the legal subject or substance of which the rights and duties are attributes. An individual human being considered to be having such attributes is what lawyers call a "natural person." According to Black's Law Dictionary, a person is:
In general usage, a human being (i.e. natural person), though by statute term may include a firm, labor organizations, partnerships, associations, corporations, legal representatives, trustees, trustees in bankruptcy, or receivers.
As an application of social psychology and other disciplines, phenomena such as the perception and attribution of personhood have been scientifically studied. Typical questions addressed in social psychology are the accuracy of attribution, processes of perception and the formation of bias. Various other scientific/medical disciplines address the myriad of issues in the development of personality.