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The mind is the set of faculties responsible for all mental
phenomena A phenomenon ( : phenomena) is an observable event. The term came into its modern philosophical usage through Immanuel Kant, who contrasted it with the noumenon, which ''cannot'' be directly observed. Kant was heavily influenced by Gottfried W ...
. Often the term is also identified with the phenomena themselves. These faculties include
thought In their most common sense, the terms thought and thinking refer to conscious cognitive processes that can happen independently of sensory stimulation. Their most paradigmatic forms are judging, reasoning, concept formation, problem solving, a ...
,
imagination Imagination is the production or simulation of novel objects, sensations, and ideas in the mind without any immediate input of the senses. Stefan Szczelkun characterises it as the forming of experiences in one's mind, which can be re-creations ...
, memory,
will Will may refer to: Common meanings * Will and testament, instructions for the disposition of one's property after death * Will (philosophy), or willpower * Will (sociology) * Will, volition (psychology) * Will, a modal verb - see Shall and will ...
, and sensation. They are responsible for various mental phenomena, like perception, pain experience, belief,
desire Desires are states of mind that are expressed by terms like "wanting", "wishing", "longing" or "craving". A great variety of features is commonly associated with desires. They are seen as propositional attitudes towards conceivable states of aff ...
,
intention Intentions are mental states in which the agent commits themselves to a course of action. Having the plan to visit the zoo tomorrow is an example of an intention. The action plan is the ''content'' of the intention while the commitment is the ''a ...
, and emotion. Various overlapping classifications of mental phenomena have been proposed. Important distinctions group them according to whether they are ''sensory'', ''propositional'', ''intentional'', ''conscious'', or ''occurrent''. Minds were traditionally understood as substances but it is more common in the contemporary perspective to conceive them as properties or capacities possessed by humans and higher animals. Various competing definitions of the exact nature of the mind or mentality have been proposed. ''Epistemic definitions'' focus on the privileged epistemic access the subject has to these states. ''Consciousness-based approaches'' give primacy to the conscious mind and allow unconscious mental phenomena as part of the mind only to the extent that they stand in the right relation to the conscious mind. According to ''intentionality-based approaches'', the power to refer to objects and to represent the world is the mark of the mental. For ''behaviorism'', whether an entity has a mind only depends on how it behaves in response to external stimuli while ''functionalism'' defines mental states in terms of the causal roles they play. Central questions for the study of mind, like whether other entities besides humans have minds or how the relation between body and mind is to be conceived, are strongly influenced by the choice of one's definition. Mind or mentality is usually contrasted with body, matter or physicality. The issue of the nature of this contrast and specifically the relation between mind and brain is called the mind-body problem. Traditional viewpoints included
dualism Dualism most commonly refers to: * Mind–body dualism, a philosophical view which holds that mental phenomena are, at least in certain respects, not physical phenomena, or that the mind and the body are distinct and separable from one another ** ...
and idealism, which consider the mind to be non-physical. Modern views often center around
physicalism In philosophy, physicalism is the metaphysical thesis that "everything is physical", that there is "nothing over and above" the physical, or that everything supervenes on the physical. Physicalism is a form of ontological monism—a "one substanc ...
and functionalism, which hold that the mind is roughly identical with the brain or reducible to physical phenomena such as neuronal activity though dualism and idealism continue to have many supporters. Another question concerns which types of
being In metaphysics, ontology is the philosophical study of being, as well as related concepts such as existence, becoming, and reality. Ontology addresses questions like how entities are grouped into categories and which of these entities exis ...
s are capable of having minds. For example, whether mind is exclusive to humans, possessed also by some or all animals, by all living things, whether it is a strictly definable characteristic at all, or whether mind can also be a property of some types of human-made machines. Different cultural and religious traditions often use different concepts of mind, resulting in different answers to these questions. Some see mind as a property exclusive to humans whereas others ascribe properties of mind to non-living entities (e.g.
panpsychism In the philosophy of mind, panpsychism () is the view that the mind or a mindlike aspect is a fundamental and ubiquitous feature of reality. It is also described as a theory that "the mind is a fundamental feature of the world which exists thro ...
and animism), to animals and to
deities A deity or god is a supernatural being who is considered divine or sacred. The ''Oxford Dictionary of English'' defines deity as a god or goddess, or anything revered as divine. C. Scott Littleton defines a deity as "a being with powers greate ...
. Some of the earliest recorded speculations linked mind (sometimes described as identical with soul or spirit) to theories concerning both life after death, and cosmological and natural order, for example in the doctrines of Zoroaster, the Buddha, Plato, Aristotle, and other ancient Greek, Indian and, later,
Islamic Islam (; ar, ۘالِإسلَام, , ) is an Abrahamic monotheistic religion centred primarily around the Quran, a religious text considered by Muslims to be the direct word of God (or '' Allah'') as it was revealed to Muhammad, the mai ...
and medieval European philosophers. Psychologists such as
Freud Sigmund Freud ( , ; born Sigismund Schlomo Freud; 6 May 1856 – 23 September 1939) was an Austrian neurologist and the founder of psychoanalysis, a clinical method for evaluating and treating pathologies explained as originating in conflicts in ...
and
James James is a common English language surname and given name: *James (name), the typically masculine first name James * James (surname), various people with the last name James James or James City may also refer to: People * King James (disambiguat ...
, and
computer scientists Computer science is the study of computation, automation, and information. Computer science spans theoretical disciplines (such as algorithms, theory of computation, information theory, and automation) to practical disciplines (including th ...
such as Turing developed influential theories about the nature of the mind. The possibility of nonbiological minds is explored in the field of artificial intelligence, which works closely in relation with
cybernetics Cybernetics is a wide-ranging field concerned with circular causality, such as feedback, in regulatory and purposive systems. Cybernetics is named after an example of circular causal feedback, that of steering a ship, where the helmsperson m ...
and
information theory Information theory is the scientific study of the quantification (science), quantification, computer data storage, storage, and telecommunication, communication of information. The field was originally established by the works of Harry Nyquist a ...
to understand the ways in which information processing by nonbiological machines is comparable or different to mental phenomena in the human mind. The mind is also sometimes portrayed as the stream of consciousness where sense impressions and mental phenomena are constantly changing.


Etymology

The original meaning of
Old English Old English (, ), or Anglo-Saxon, is the earliest recorded form of the English language, spoken in England and southern and eastern Scotland in the early Middle Ages. It was brought to Great Britain by Anglo-Saxon settlement of Britain, Anglo ...
'' gemynd'' was the faculty of memory, not of thought in general. Hence ''call to mind'', ''come to mind'', ''keep in mind'', ''to have mind of'', etc. The word retains this sense in Scotland.
Old English Old English (, ), or Anglo-Saxon, is the earliest recorded form of the English language, spoken in England and southern and eastern Scotland in the early Middle Ages. It was brought to Great Britain by Anglo-Saxon settlement of Britain, Anglo ...
had other words to express "mind", such as '' hyge'' "mind, spirit". The meaning of "memory" is shared with Old Norse, which has '' munr''. The word is originally from a
PIE A pie is a baked dish which is usually made of a pastry dough casing that contains a filling of various sweet or savoury ingredients. Sweet pies may be filled with fruit (as in an apple pie), nuts ( pecan pie), brown sugar ( sugar pie), swe ...
verbal root ', meaning "to think, remember", whence also Latin'' mens'' "mind", Sanskrit '' '' "mind" and Greek μένος "mind, courage, anger". The generalization of ''mind'' to include all mental faculties, thought, volition, feeling and memory, gradually develops over the 14th and 15th centuries.


Definitions

The mind is often understood as a faculty that manifests itself in mental phenomena like sensation, perception, thinking, reasoning, memory, belief, desire, emotion and motivation. Mind or mentality is usually contrasted with body, matter or physicality. Central to this contrast is the intuition that minds exhibit various features not found in and maybe even incompatible with the material universe as described by the natural sciences. On the traditionally dominant substantialist view associated with René Descartes, minds are defined as independent thinking substances. But it is more common in contemporary philosophy to conceive minds not as substances but as properties or capacities possessed by humans and higher animals. Despite this agreement, there is still a lot of difference of opinion concerning what the exact nature of mind is and various competing definitions have been proposed. Philosophical definitions of mind usually proceed not just by listing various types of phenomena belonging to the mind but by searching the "mark of the mental": a feature that is shared by all mental states and only by mental states. ''Epistemic approaches'' define mental states in terms of the privileged epistemic access the subject has to these states. This is often combined with a ''consciousness-based approach'', which emphasizes the primacy of consciousness in relation to mind. ''Intentionality-based approaches'', on the other hand, see the power of minds to refer to objects and represent the world as being a certain way as the ''mark of the mental''. According to ''behaviorism'', whether an entity has a mind only depends on how it behaves in response to external stimuli while ''functionalism'' defines mental states in terms of the causal roles they play. The differences between these diverse approaches are substantial since they result in very different answers to questions like whether animals or computers have minds. There is a great variety of mental states. They fall into categories like sensory and non-sensory or conscious and unconscious. Various of the definitions listed above excel for states from one category but struggle to account for why states from another category are also part of the mind. This has led some theorists to doubt that there is a ''mark of the mental''. So maybe the term "mind" just refers to a cluster of loosely related ideas that do not share one unifying feature. Some theorists have responded to this by narrowing their definitions of mind to "higher" intellectual faculties, like thinking, reasoning and memory. Others try to be as inclusive as possible regarding "lower" intellectual faculties, like sensing and emotion. In popular usage, ''mind'' is frequently synonymous with ''thought'': the private conversation with ourselves that we carry on "inside our heads". Thus we "make up our minds", "change our minds" or are "of two minds" about something. One of the key attributes of the mind in this sense is that it is a private sphere to which no one but the owner has access. No one else can "know our mind". They can only interpret what we consciously or unconsciously communicate.


Epistemic and consciousness-based approaches

''
Epistemic Epistemology (; ), or the theory of knowledge, is the branch of philosophy concerned with knowledge. Epistemology is considered a major subfield of philosophy, along with other major subfields such as ethics, logic, and metaphysics. Episte ...
approaches'' emphasize that the subject has privileged access to all or at least some of their mental states. It is sometimes claimed that this access is ''direct'', ''private'' and ''infallible''. ''Direct access'' refers to non-inferential knowledge. When someone is in pain, for example, they know directly that they are in pain, they do not need to infer it from other indicators like a body part being swollen or their tendency to scream when it is touched. But we arguably also have non-inferential knowledge of external objects, like trees or cats, through perception, which is why this criterion by itself is not sufficient. Another epistemic privilege often mentioned is that mental states are ''private'' in contrast to ''public'' external facts. For example, the fallen tree lying on a person's leg is directly open to perception by the bystanders while the victim's pain is private: only they know it directly while the bystanders have to infer it from their screams. It was traditionally often claimed that we have infallible knowledge of our own mental states, i.e. that we cannot be wrong about them when we have them. So when someone has an itching sensation, for example, they cannot be wrong about having this sensation. They can only be wrong about the non-mental causes, e.g. whether it is the consequence of bug bites or of a fungal infection. But various counterexamples have been presented to claims of infallibility, which is why this criterion is usually not accepted in contemporary philosophy. One problem for all ''epistemic approaches'' to the ''mark of the mental'' is that they focus mainly on conscious states but exclude unconscious states. A repressed
desire Desires are states of mind that are expressed by terms like "wanting", "wishing", "longing" or "craving". A great variety of features is commonly associated with desires. They are seen as propositional attitudes towards conceivable states of aff ...
, for example, is a mental state to which the subject lacks the forms of privileged epistemic access mentioned. One way to respond to this worry is to ascribe a privileged status to conscious mental states. On such a ''consciousness-based approach'', conscious mental states are non-derivative constituents of the mind while unconscious states somehow depend on their conscious counterparts for their existence. An influential example of this position is due to
John Searle John Rogers Searle (; born July 31, 1932) is an American philosopher widely noted for contributions to the philosophy of language, philosophy of mind, and social philosophy. He began teaching at UC Berkeley in 1959, and was Willis S. and Mario ...
, who holds that unconscious mental states have to be accessible to consciousness to count as "mental" at all. They can be understood as dispositions to bring about conscious states. This position denies that the so-called "deep unconscious", i.e. mental contents inaccessible to consciousness, exists. Another problem for ''consciousness-based approaches'', besides the issue of accounting for the unconscious mind, is to elucidate the nature of consciousness itself. Consciousness-based approaches are usually interested in ''
phenomenal consciousness Consciousness, at its simplest, is sentience and awareness of internal and external existence. However, the lack of definitions has led to millennia of analyses, explanations and debates by philosophers, theologians, linguisticians, and scient ...
'', i.e. in qualitative experience, rather than '' access consciousness'', which refers to information being available for reasoning and guiding behavior. Conscious mental states are normally characterized as qualitative and subjective, i.e. that there is something it is like for a subject to be in these states. Opponents of consciousness-based approaches often point out that despite these attempts, it is still very unclear what the term "phenomenal consciousness" is supposed to mean. This is important because not much would be gained theoretically by defining one ill-understood term in terms of another. Another objection to this type of approach is to deny that the conscious mind has a privileged status in relation to the unconscious mind, for example, by insisting that the deep unconscious exists.


Intentionality-based approaches

''Intentionality-based approaches'' see
intentionality ''Intentionality'' is the power of minds to be about something: to represent or to stand for things, properties and states of affairs. Intentionality is primarily ascribed to mental states, like perceptions, beliefs or desires, which is why it ha ...
as the ''mark of the mental''. The originator of this approach is Franz Brentano, who defined intentionality as the characteristic of mental states to refer to or be about objects. One central idea for this approach is that minds represent the world around them, which is not the case for regular physical objects. So a person who believes that there is ice cream in the fridge represents the world as being a certain way. The ice cream can be represented but it does not itself represent the world. This is why a mind is ascribed to the person but not to the ice cream, according to the intentional approach. One advantage of it in comparison to the ''epistemic approach'' is that it has no problems to account for unconscious mental states: they can be intentional just like conscious mental states and thereby qualify as constituents of the mind. But a problem for this approach is that there are also some non-mental entities that have intentionality, like maps or linguistic expressions. One response to this problem is to hold that the intentionality of non-mental entities is somehow derivative in relation to the intentionality of mental entities. For example, a map of Addis Ababa may be said to represent Addis Ababa not intrinsically but only extrinsically because people ''interpret'' it as a representation. Another difficulty is that not all mental states seem to be intentional. So while beliefs and desires are forms of representation, this seems not to be the case for pains and itches, which may ''indicate'' a problem without ''representing'' it. But some theorists have argued that even these apparent counterexamples should be considered intentional when properly understood.


Behaviorism and functionalism

'' Behaviorist'' definitions characterize mental states as dispositions to engage in certain publicly observable behavior as a reaction to particular external stimuli. On this view, to ascribe a belief to someone is to describe the tendency of this person to behave in certain ways. Such an ascription does not involve any claims about the internal states of this person, it only talks about behavioral tendencies. A strong motivation for such a position comes from empiricist considerations stressing the importance of observation and the lack thereof in the case of private internal mental states. This is sometimes combined with the thesis that we could not even learn how to use mental terms without reference to the behavior associated with them. One problem for behaviorism is that the same entity often behaves differently despite being in the same situation as before. This suggests that explanation needs to make reference to the internal states of the entity that mediate the link between stimulus and response. This problem is avoided by functionalist approaches, which define mental states through their causal roles but allow both external and internal events in their causal network. On this view, the definition of pain-state may include aspects such as being in a state that "tends to be caused by bodily injury, to produce the belief that something is wrong with the body and ... to cause wincing or moaning". One important aspect of both behaviorist and functionalist approaches is that, according to them, the mind is '' multiply realizable''. This means that it does not depend on the exact constitution of an entity for whether it has a mind or not. Instead, only its behavioral dispositions or its role in the causal network matter. The entity in question may be a human, an animal, a silicon-based alien or a robot. Functionalists sometimes draw an analogy to the software-hardware distinction where the mind is likened to a certain type of software that can be installed on different forms of hardware. Closely linked to this analogy is the thesis of computationalism, which defines the mind as an information processing system that is physically implemented by the neural activity of the brain. One problem for all of these views is that they seem to be unable to account for the phenomenal consciousness of the mind emphasized by ''consciousness-based approaches''. It may be true that pains are caused by bodily injuries and themselves produce certain beliefs and moaning behavior. But the causal profile of pain remains silent on the intrinsic unpleasantness of the painful experience itself. Some states that are not painful to the subject at all may even fit these characterizations.


Forms


Mental faculties

Broadly speaking, mental faculties are the various functions of the mind, or things the mind can "do".
Thought In their most common sense, the terms thought and thinking refer to conscious cognitive processes that can happen independently of sensory stimulation. Their most paradigmatic forms are judging, reasoning, concept formation, problem solving, a ...
is a mental act that allows humans to make sense of things in the world, and to represent and interpret them in ways that are significant, or which accord with their needs, attachments, goals, commitments, plans, ends, desires, etc. Thinking involves the
symbol A symbol is a mark, sign, or word that indicates, signifies, or is understood as representing an idea, object, or relationship. Symbols allow people to go beyond what is known or seen by creating linkages between otherwise very different conc ...
ic or
semiotic Semiotics (also called semiotic studies) is the systematic study of sign processes ( semiosis) and meaning making. Semiosis is any activity, conduct, or process that involves signs, where a sign is defined as anything that communicates something ...
mediation of ideas or data, as when we form concepts, engage in
problem solving Problem solving is the process of achieving a goal by overcoming obstacles, a frequent part of most activities. Problems in need of solutions range from simple personal tasks (e.g. how to turn on an appliance) to complex issues in business an ...
, reasoning, and making decisions. Words that refer to similar concepts and processes include
deliberation Deliberation is a process of thoughtfully weighing options, usually prior to voting. Deliberation emphasizes the use of logic and reason as opposed to power-struggle, creativity, or dialogue. Group decisions are generally made after deliberation ...
,
cognition Cognition refers to "the mental action or process of acquiring knowledge and understanding through thought, experience, and the senses". It encompasses all aspects of intellectual functions and processes such as: perception, attention, thought, ...
, ideation,
discourse Discourse is a generalization of the notion of a conversation to any form of communication. Discourse is a major topic in social theory, with work spanning fields such as sociology, anthropology, continental philosophy, and discourse analysis. ...
and
imagination Imagination is the production or simulation of novel objects, sensations, and ideas in the mind without any immediate input of the senses. Stefan Szczelkun characterises it as the forming of experiences in one's mind, which can be re-creations ...
. Thinking is sometimes described as a "higher"
cognitive Cognition refers to "the mental action or process of acquiring knowledge and understanding through thought, experience, and the senses". It encompasses all aspects of intellectual functions and processes such as: perception, attention, thought, ...
function and the analysis of thinking processes is a part of
cognitive psychology Cognitive psychology is the scientific study of mental processes such as attention, language use, memory, perception, problem solving, creativity, and reasoning. Cognitive psychology originated in the 1960s in a break from behaviorism, which ...
. It is also deeply connected with our capacity to make and use
tools A tool is an object that can extend an individual's ability to modify features of the surrounding environment or help them accomplish a particular task. Although many animals use simple tools, only human beings, whose use of stone tools dates ba ...
; to understand
cause and effect Causality (also referred to as causation, or cause and effect) is influence by which one event, process, state, or object (''a'' ''cause'') contributes to the production of another event, process, state, or object (an ''effect'') where the cau ...
; to recognize patterns of significance; to comprehend and
disclose Disclose were a Japanese punk rock band from Kōchi City, heavily influenced by Discharge. Their sound heavily replicates Discharge's style, with an increased use of fuzz and distortion guitar effects. The subject matter is also similar to Di ...
unique contexts of experience or activity; and to respond to the world in a meaningful way. Memory is the ability to preserve, retain and subsequently recall knowledge, information, or experience. Although memory has traditionally been a persistent theme in
philosophy Philosophy (from , ) is the systematized study of general and fundamental questions, such as those about existence, reason, knowledge, values, mind, and language. Such questions are often posed as problems to be studied or resolved. Some ...
, the late nineteenth and early twentieth centuries also saw the study of memory emerge as a subject of inquiry within the paradigms of
cognitive psychology Cognitive psychology is the scientific study of mental processes such as attention, language use, memory, perception, problem solving, creativity, and reasoning. Cognitive psychology originated in the 1960s in a break from behaviorism, which ...
. In recent decades, it has become one of the pillars of a new branch of science called cognitive neuroscience, a marriage between
cognitive psychology Cognitive psychology is the scientific study of mental processes such as attention, language use, memory, perception, problem solving, creativity, and reasoning. Cognitive psychology originated in the 1960s in a break from behaviorism, which ...
and neuroscience.
Imagination Imagination is the production or simulation of novel objects, sensations, and ideas in the mind without any immediate input of the senses. Stefan Szczelkun characterises it as the forming of experiences in one's mind, which can be re-creations ...
is the activity of generating or evoking novel situations,
image An image is a visual representation of something. It can be two-dimensional, three-dimensional, or somehow otherwise feed into the visual system to convey information. An image can be an artifact, such as a photograph or other two-dimensiona ...
s, ideas or other qualia in the mind. It is a characteristically subjective ''activity'', rather than a direct or passive experience. The term is technically used in psychology for the process of reviving in the mind
percepts Perception () is the organization, identification, and interpretation of sensory information in order to represent and understand the presented information or environment. All perception involves signals that go through the nervous system ...
of objects formerly given in sense perception. Since this use of the term conflicts with that of ordinary language, some psychologists have preferred to describe this process as " imaging" or "
imagery Imagery is visual symbolism, or figurative language that evokes a mental image or other kinds of sense impressions, especially in a literary work, but also in other activities such as psychotherapy. Forms There are five major types of sensory ima ...
" or to speak of it as "reproductive" as opposed to "productive" or "constructive" imagination. Things imagined are said to be seen in the "
mind's eye A mental image is an experience that, on most occasions, significantly resembles the experience of 'perceiving' some object, event, or scene, but occurs when the relevant object, event, or scene is not actually present to the senses. There are ...
". Among the many practical functions of imagination are the ability to project possible futures (or histories), to "see" things from another's perspective, and to change the way something is perceived, including to make decisions to respond to, or enact, what is imagined. Consciousness in
mammal Mammals () are a group of vertebrate animals constituting the class Mammalia (), characterized by the presence of mammary glands which in females produce milk for feeding (nursing) their young, a neocortex (a region of the brain), fur or ...
s (this includes humans) is an aspect of the mind generally thought to comprise qualities such as
subjectivity Subjectivity in a philosophical context has to do with a lack of objective reality. Subjectivity has been given various and ambiguous definitions by differing sources as it is not often the focal point of philosophical discourse.Bykova, Marina F ...
,
sentience Sentience is the capacity to experience feelings and sensations. The word was first coined by philosophers in the 1630s for the concept of an ability to feel, derived from Latin '':wikt:sentientem, sentientem'' (a feeling), to distinguish it fro ...
, and the ability to perceive the relationship between oneself and one's
environment Environment most often refers to: __NOTOC__ * Natural environment, all living and non-living things occurring naturally * Biophysical environment, the physical and biological factors along with their chemical interactions that affect an organism or ...
. It is a subject of much research in philosophy of mind, psychology, neuroscience, and cognitive science. Some philosophers divide consciousness into
phenomena A phenomenon ( : phenomena) is an observable event. The term came into its modern philosophical usage through Immanuel Kant, who contrasted it with the noumenon, which ''cannot'' be directly observed. Kant was heavily influenced by Gottfried W ...
l consciousness, which is subjective experience itself, and access consciousness, which refers to the global availability of information to processing systems in the brain.Ned Block: "On a Confusion about a Function of Consciousness" in: ''The Behavioral and Brain Sciences'', 1995. Phenomenal consciousness has many different experienced qualities, often referred to as qualia. Phenomenal consciousness is usually consciousness ''of'' something or ''about'' something, a property known as
intentionality ''Intentionality'' is the power of minds to be about something: to represent or to stand for things, properties and states of affairs. Intentionality is primarily ascribed to mental states, like perceptions, beliefs or desires, which is why it ha ...
in philosophy of mind.


Categories of mental phenomena

The mental phenomena brought about by the faculties of the mind have been categorized according to various distinctions. Important distinctions group mental phenomena together according to whether they are ''sensory'', ''qualitative'', ''propositional'', ''intentional'', ''conscious'', ''occurrent'' or ''rational''. These different distinctions result in overlapping categorizations. Some mental phenomena, like perception or bodily awareness, are ''sensory'', i.e. based on the
senses A sense is a biological system used by an organism for sensation, the process of gathering information about the world through the detection of stimuli. (For example, in the human body, the brain which is part of the central nervous system rec ...
. These phenomena are of special interest to empiricists, who hold that they are our only source of knowledge about the external world. They are contrasted with ''non-sensory'' phenomena like thoughts or beliefs, which do not involve sense impressions. Sensory states are closely related to ''qualitative states'', which have qualia and are therefore associated with a subjective feeling of what it is like to be in this state. Sensory and qualitative states are often contrasted with '' propositional states'', which are sometimes said to be non-sensory and non-qualitative. Propositional states involve attitudes, like belief or
desire Desires are states of mind that are expressed by terms like "wanting", "wishing", "longing" or "craving". A great variety of features is commonly associated with desires. They are seen as propositional attitudes towards conceivable states of aff ...
, which a subject has towards a proposition. One problem with this contrast is that some propositional attitudes may have a subjective feeling to them, which would make them qualitative phenomena. This is the case, for example, when actively desiring something. Another problem with this contrast is that some mental phenomena, like perceptions, are both sensory and propositional. Propositional attitudes are '' intentional states'', which have as their characteristic that they refer to or are about objects or states of affairs. Some philosophers see intentionality as the mark of the mental, i.e. as what is shared by all and only by mental phenomena. Opponents of this position have argued that there are various mental phenomena, like pains and itches, that lack the representational aspect associated with intentionality and therefore count as non-intentional. This claim is sometimes even extended to all sensory phenomena. It sometimes held that all intentional states are propositional. While this is true for the paradigmatic cases, it has been argued that there is a form of object-directed intentionality, like the fear of snakes, that does not involve propositional attitudes, like the fear that one will be bitten by snakes. Another important distinction among mental states is whether they are '' conscious'' or not. Often two types of consciousness are distinguished: '' phenomenal consciousness and access consciousness''. ''Phenomenal consciousness'' refers to actual experience. A common view is that some states, like sensations or pains, are necessarily associated with phenomenal consciousness while other states, like beliefs and desires, can be present both with and without phenomenal consciousness. According to some views, conscious mental states are more basic while unconscious states only count as mental if they can arise in phenomenal consciousness. ''Access consciousness'', on the other hand, refers to mental states that are accessible: they carry information that is available for reasoning and guiding behavior. This notion is closely related to ''occurrent mental states'', which are not just accessible but also currently active or causally efficacious within the owner's mind. All phenomenally conscious mental states are occurrent but there may also be unconscious occurrent states, like repressed desires, that influence our behavior. Occurrent mental states contrast with ''standing'' or ''dispositional mental states'', which are part of the subject's mind even though they currently play no role in it. Mental phenomena are '' rational'' if they are well justified or obey the norms of rationality. '' Irrational mental phenomena'', on the other hand, violate these norms. But not all mental phenomena are rationally evaluable: some are ''arational'' and exist outside the domain of rationality. They include urges, dizziness or hunger while beliefs and
intention Intentions are mental states in which the agent commits themselves to a course of action. Having the plan to visit the zoo tomorrow is an example of an intention. The action plan is the ''content'' of the intention while the commitment is the ''a ...
s are the paradigmatic examples of rationally evaluable states. Some hold that rationality depends only on structural principles that govern how different mental states should relate to each other while others define rationality in terms of responding correctly to reasons.


Mental contents

Mental contents are those items that are thought of as being "in" the mind, and capable of being formed and manipulated by mental processes and faculties. Examples include
thought In their most common sense, the terms thought and thinking refer to conscious cognitive processes that can happen independently of sensory stimulation. Their most paradigmatic forms are judging, reasoning, concept formation, problem solving, a ...
s, concepts, memories, emotions,
percept Perception () is the organization, identification, and interpretation of sensory information in order to represent and understand the presented information or environment. All perception involves signals that go through the nervous system ...
s and
intention Intentions are mental states in which the agent commits themselves to a course of action. Having the plan to visit the zoo tomorrow is an example of an intention. The action plan is the ''content'' of the intention while the commitment is the ''a ...
s. Philosophical theories of mental content include internalism,
externalism Externalism is a group of positions in the philosophy of mind which argues that the conscious mind is not only the result of what is going on inside the nervous system (or the brain), but also what ''occurs'' or ''exists'' outside the subject. It i ...
,
representationalism In the philosophy of perception and philosophy of mind, the question of direct or naïve realism, as opposed to indirect or representational realism, is the debate over the nature of conscious experience;Lehar, Steve. (2000)The Function of Consc ...
and
intentionality ''Intentionality'' is the power of minds to be about something: to represent or to stand for things, properties and states of affairs. Intentionality is primarily ascribed to mental states, like perceptions, beliefs or desires, which is why it ha ...
.
Memetics Memetics is a study of information and culture. While memetics originated as an analogy with Darwinian evolution, digital communication, media, and sociology scholars have also adopted the term "memetics" to describe an established empirical study ...
is a theory of mental content based on an analogy with Darwinian evolution, which was originated by
Richard Dawkins Richard Dawkins (born 26 March 1941) is a British evolutionary biologist and author. He is an emeritus fellow of New College, Oxford and was Professor for Public Understanding of Science in the University of Oxford from 1995 to 2008. An ath ...
and
Douglas Hofstadter Douglas Richard Hofstadter (born February 15, 1945) is an American scholar of cognitive science, physics, and comparative literature whose research includes concepts such as the sense of self in relation to the external world, consciousness, an ...
in the 1980s. It is an
evolutionary model A number of different Markov models of DNA sequence evolution have been proposed. These substitution models differ in terms of the parameters used to describe the rates at which one nucleotide replaces another during evolution. These models are ...
of cultural
information transfer In telecommunications, information transfer is the process of moving messages containing user information from a source to a sink via a communication channel. In this sense, information transfer is equivalent to data transmission which highlights ...
. A
meme A meme ( ) is an idea, behavior, or style that spreads by means of imitation from person to person within a culture and often carries symbolic meaning representing a particular phenomenon or theme. A meme acts as a unit for carrying cultural i ...
, analogous to a gene, is an idea, belief, pattern of behaviour (etc.) "hosted" in one or more individual minds, and can reproduce itself from mind to mind. Thus what would otherwise be regarded as one individual influencing another to adopt a belief, is seen memetically as a meme reproducing itself.


Relation to the brain

In animals, the brain, or ''encephalon'' ( Greek for "in the head"), is the control center of the central nervous system, responsible for
thought In their most common sense, the terms thought and thinking refer to conscious cognitive processes that can happen independently of sensory stimulation. Their most paradigmatic forms are judging, reasoning, concept formation, problem solving, a ...
. In most animals, the brain is located in the head, protected by the skull and close to the primary sensory apparatus of vision, hearing, equilibrioception, taste and
olfaction The sense of smell, or olfaction, is the special sense through which smells (or odors) are perceived. The sense of smell has many functions, including detecting desirable foods, hazards, and pheromones, and plays a role in taste. In humans, it ...
. While all vertebrates have a brain, most invertebrates have either a centralized brain or collections of individual
ganglia A ganglion is a group of neuron cell bodies in the peripheral nervous system. In the somatic nervous system this includes dorsal root ganglia and trigeminal ganglia among a few others. In the autonomic nervous system there are both sympatheti ...
. Primitive animals such as sponges do not have a brain at all. Brains can be extremely complex. For example, the human brain contains around 86 billion neurons, each linked to as many as 10,000 others. Understanding the relationship between the brain and the mind –the mind–body problem – is one of the central issues in the history of
philosophy Philosophy (from , ) is the systematized study of general and fundamental questions, such as those about existence, reason, knowledge, values, mind, and language. Such questions are often posed as problems to be studied or resolved. Some ...
, a challenging problem both philosophically and scientifically. There are three major philosophical schools of thought concerning the answer: dualism, materialism, and idealism.
Dualism Dualism most commonly refers to: * Mind–body dualism, a philosophical view which holds that mental phenomena are, at least in certain respects, not physical phenomena, or that the mind and the body are distinct and separable from one another ** ...
holds that the mind exists independently of the brain;
materialism Materialism is a form of philosophical monism which holds matter to be the fundamental substance in nature, and all things, including mental states and consciousness, are results of material interactions. According to philosophical materiali ...
holds that mental phenomena are identical to neuronal phenomena;A.R. Lacey, ''A Dictionary of Philosophy'', 1996 and idealism holds that only mental phenomena exist. Through most of history many philosophers found it inconceivable that cognition could be implemented by a physical substance such as brain tissue (that is neurons and synapses). Descartes, who thought extensively about mind-brain relationships, found it possible to explain reflexes and other simple behaviors in mechanistic terms, although he did not believe that complex thought, especially language, could be explained by reference to the physical brain alone. The most straightforward scientific evidence of a strong relationship between the physical brain matter and the mind is the impact physical alterations to the brain have on the mind, such as with traumatic brain injury and psychoactive drug use. Philosopher Patricia Churchland notes that drug-mind interaction indicates an intimate connection between the brain and the mind. In addition to the philosophical questions, the relationship between mind and brain involves a number of scientific questions, including understanding the relationship between mental activity and brain activity, the exact mechanisms by which drugs influence
cognition Cognition refers to "the mental action or process of acquiring knowledge and understanding through thought, experience, and the senses". It encompasses all aspects of intellectual functions and processes such as: perception, attention, thought, ...
, and the neural correlates of consciousness. Theoretical approaches to explain how mind emerges from the brain include connectionism, computationalism and
Bayesian brain Bayesian approaches to brain function investigate the capacity of the nervous system to operate in situations of uncertainty in a fashion that is close to the optimal prescribed by Bayesian statistics. This term is used in behavioural sciences and n ...
.


Evolution

The
evolution of human intelligence The evolution of human intelligence is closely tied to the evolution of the human brain and to the origin of language. The timeline of human evolution spans approximately seven million years, from the separation of the genus '' Pan'' until the em ...
refers to several theories that aim to describe how human intelligence has evolved in relation to the evolution of the human brain and the
origin of language The origin of language (spoken and signed, as well as language-related technological systems such as writing), its relationship with human evolution, and its consequences have been subjects of study for centuries. Scholars wishing to study th ...
. The timeline of human evolution spans some 7 million years, from the separation of the genus '' Pan'' until the emergence of behavioral modernity by 50,000 years ago. Of this timeline, the first 3 million years concern '' Sahelanthropus'', the following 2 million concern '' Australopithecus'', while the final 2 million span the history of actual '' Homo'' species (the
Paleolithic The Paleolithic or Palaeolithic (), also called the Old Stone Age (from Greek: παλαιός ''palaios'', "old" and λίθος ''lithos'', "stone"), is a period in human prehistory that is distinguished by the original development of stone too ...
). Many traits of human intelligence, such as empathy, theory of mind, mourning, ritual, and the use of
symbols A symbol is a mark, sign, or word that indicates, signifies, or is understood as representing an idea, object, or relationship. Symbols allow people to go beyond what is known or seen by creating linkages between otherwise very different conc ...
and tools, are already apparent in great apes although in lesser sophistication than in humans. There is a debate between supporters of the idea of a sudden emergence of intelligence, or "
Great leap forward The Great Leap Forward (Second Five Year Plan) of the People's Republic of China (PRC) was an economic and social campaign led by the Chinese Communist Party (CCP) from 1958 to 1962. CCP Chairman Mao Zedong launched the campaign to reconstruc ...
" and those of a gradual or continuum hypothesis. Theories of the evolution of intelligence include: * Robin Dunbar's social brain hypothesis * Geoffrey Miller's sexual selection hypothesis concerning Sexual selection in human evolution * The ecological dominance-social competition (EDSC) explained by Mark V. Flinn, David C. Geary and Carol V. Ward based mainly on work by
Richard D. Alexander Richard D. Alexander (November 18, 1929 – August 20, 2018) was an American zoologist who was a professor at the University of Michigan and curator at the university's museum of zoology of in Ann Arbor, Michigan. His scientific pursuits integra ...
. * The idea of intelligence as a signal of good health and resistance to disease. * The Group selection theory contends that organism characteristics that provide benefits to a group (clan, tribe, or larger population) can evolve despite individual disadvantages such as those cited above. * The idea that intelligence is connected with nutrition, and thereby with status. A higher IQ could be a signal that an individual comes from and lives in a physical and social environment where nutrition levels are high, and vice versa.


Philosophy

Philosophy of mind is the branch of
philosophy Philosophy (from , ) is the systematized study of general and fundamental questions, such as those about existence, reason, knowledge, values, mind, and language. Such questions are often posed as problems to be studied or resolved. Some ...
that studies the nature of the mind, mental events,
mental function Cognition refers to "the mental action or process of acquiring knowledge and understanding through thought, experience, and the senses". It encompasses all aspects of intellectual functions and processes such as: perception, attention, thought, ...
s,
mental properties A mental state, or a mental property, is a state of mind of a person. Mental states comprise a diverse class, including perception, pain experience, belief, desire, intention, emotion, and memory. There is controversy concerning the exact definiti ...
, consciousness and their relationship to the physical body. The '' mind–body problem'', i.e. the relationship of the mind to the body, is commonly seen as the central issue in philosophy of mind, although there are other issues concerning the nature of the mind that do not involve its relation to the physical body.
José Manuel Rodriguez Delgado José is a predominantly Spanish and Portuguese language, Portuguese form of the given name Joseph. While spelled alike, this name is pronounced differently in each language: Spanish ; Portuguese (or ). In French, the name ''José'', pronounced ...
writes, "In present popular usage, soul and mind are not clearly differentiated and some people, more or less consciously, still feel that the soul, and perhaps the mind, may enter or leave the body as independent entities." ''
Dualism Dualism most commonly refers to: * Mind–body dualism, a philosophical view which holds that mental phenomena are, at least in certain respects, not physical phenomena, or that the mind and the body are distinct and separable from one another ** ...
'' and '' monism'' are the two major schools of thought that attempt to resolve the mind–body problem. Dualism is the position that mind and body are in some way separate from each other. It can be traced back to Plato, AristotleRobinson, H. (1983): ‘Aristotelian dualism’, Oxford Studies in Ancient Philosophy 1, 123–44. and the
Nyaya (Sanskrit: न्याय, ''nyā-yá''), literally meaning "justice", "rules", "method" or "judgment",Samkhya ''Samkhya'' or ''Sankya'' (; Sanskrit सांख्य), IAST: ') is a Dualism (Indian philosophy), dualistic Āstika and nāstika, school of Indian philosophy. It views reality as composed of two independent principles, ''purusha, puruṣa' ...
and Yoga schools of Hindu philosophy, but it was most precisely formulated by René Descartes in the 17th century. '' Substance dualists'' argue that the mind is an independently existing substance, whereas '' Property dualists'' maintain that the mind is a group of independent properties that
emerge Emerge may refer to: * '' Emerge: The Best of Neocolours'', the fourth album of Neocolours * Emerge Desktop, a Desktop shell replacement for Microsoft Windows * ''Emerge'' (magazine), a defunct news magazine * Emerge Stimulation Drink, a drink s ...
from and cannot be reduced to the brain, but that it is not a distinct substance.Hart, W.D. (1996) "Dualism", in Samuel Guttenplan (org) ''A Companion to the Philosophy of Mind'', Blackwell, Oxford, 265–267. The 20th century philosopher Martin Heidegger suggested that subjective experience and activity (i.e. the "mind") cannot be made sense of in terms of
Cartesian Cartesian means of or relating to the French philosopher René Descartes—from his Latinized name ''Cartesius''. It may refer to: Mathematics *Cartesian closed category, a closed category in category theory *Cartesian coordinate system, modern ...
"substances" that bear "properties" at all (whether the mind itself is thought of as a distinct, separate kind of substance or not). This is because the nature of subjective, ''qualitative'' experience is incoherent in terms of – or semantically incommensurable with the concept of – substances that bear properties. This is a fundamentally ontological argument. The philosopher of cognitive science
Daniel Dennett Daniel Clement Dennett III (born March 28, 1942) is an American philosopher, writer, and cognitive scientist whose research centers on the philosophy of mind, philosophy of science, and philosophy of biology, particularly as those fields relat ...
, for example, argues there is no such thing as a narrative center called the "mind", but that instead there is simply a collection of sensory inputs and outputs: different kinds of "software" running in parallel. Psychologist
B.F. Skinner Burrhus Frederic Skinner (March 20, 1904 – August 18, 1990) was an American psychologist, behaviorist, author, inventor, and social philosopher. He was a professor of psychology at Harvard University from 1958 until his retirement in 1974. ...
argued that the mind is an explanatory fiction that diverts attention from environmental causes of behavior; he considered the mind a "black box" and thought that mental processes may be better conceived of as forms of covert verbal behavior. Philosopher David Chalmers has argued that the third person approach to uncovering mind and consciousness is not effective, such as looking into other's brains or observing human conduct, but that a first person approach is necessary. Such a first person perspective indicates that the mind must be conceptualized as something distinct from the brain. The mind has also been described as manifesting from moment to moment, one thought moment at a time as a fast flowing stream, where sense impressions and mental phenomena are constantly changing.


Relation to the body

''Monism'' is the position that mind and body are not
physiologically Physiology (; ) is the scientific study of functions and mechanisms in a living system. As a sub-discipline of biology, physiology focuses on how organisms, organ systems, individual organs, cells, and biomolecules carry out the chemical ...
and ontologically distinct kinds of entities. This view was first advocated in Western Philosophy by
Parmenides Parmenides of Elea (; grc-gre, Παρμενίδης ὁ Ἐλεάτης; ) was a pre-Socratic Greek philosopher from Elea in Magna Graecia. Parmenides was born in the Greek colony of Elea, from a wealthy and illustrious family. His dates a ...
in the 5th Century BC and was later espoused by the 17th Century rationalist
Baruch Spinoza Baruch (de) Spinoza (born Bento de Espinosa; later as an author and a correspondent ''Benedictus de Spinoza'', anglicized to ''Benedict de Spinoza''; 24 November 1632 – 21 February 1677) was a Dutch philosopher of Portuguese-Jewish origin, b ...
.Spinoza, Baruch (1670) ''Tractatus Theologico-Politicus'' (A Theologico-Political Treatise). According to Spinoza's
dual-aspect theory : In the philosophy of mind, double-aspect theory is the view that the mental and the physical are two aspects of, or perspectives on, the same substance. It is also called dual-aspect monism, not to be confused with mind–body dualism. The theor ...
, mind and body are two aspects of an underlying reality which he variously described as "Nature" or "God". * '' Physicalists'' argue that only the entities postulated by physical theory exist, and that the mind will eventually be explained in terms of these entities as physical theory continues to evolve. * ''
Idealists In philosophy, the term idealism identifies and describes metaphysical perspectives which assert that reality is indistinguishable and inseparable from perception and understanding; that reality is a mental construct closely connected to ide ...
'' maintain that the mind is all that exists and that the external world is either mental itself, or an illusion created by the mind. * '' Neutral monists'' adhere to the position that perceived things in the world can be regarded as either physical or mental depending on whether one is interested in their relationship to other things in the world or their relationship to the perceiver. For example, a red spot on a wall is physical in its dependence on the wall and the pigment of which it is made, but it is mental in so far as its perceived redness depends on the workings of the visual system. Unlike dual-aspect theory, neutral monism does not posit a more fundamental substance of which mind and body are aspects. The most common monisms in the 20th and 21st centuries have all been variations of physicalism; these positions include
behaviorism Behaviorism is a systematic approach to understanding the behavior of humans and animals. It assumes that behavior is either a reflex evoked by the pairing of certain antecedent (behavioral psychology), antecedent stimuli in the environment, o ...
, the
type identity theory Type physicalism (also known as reductive materialism, type identity theory, mind–brain identity theory and identity theory of mind) is a physicalism, physicalist theory in the philosophy of mind. It asserts that mental events can be grouped in ...
,
anomalous monism Anomalous monism is a philosophical thesis about the mind–body relationship. It was first proposed by Donald Davidson in his 1970 paper "Mental Events". The theory is twofold and states that mental events are identical with physical events, and ...
and functionalism.Kim, J., "Mind-Body Problem", ''Oxford Companion to Philosophy''. Ted Honderich (ed.). Oxford:Oxford University Press. 1995. Many modern philosophers of mind adopt either a ''reductive'' or ''non-reductive physicalist'' position, maintaining in their different ways that the mind is not something separate from the body. These approaches have been particularly influential in the sciences, e.g. in the fields of sociobiology, computer science, evolutionary psychology and the various neurosciences.Pinel, J. ''Psychobiology'', (1990) Prentice Hall, Inc. LeDoux, J. (2002) ''The Synaptic Self: How Our Brains Become Who We Are'', New York: Viking Penguin. Dawkins, R. ''The Selfish Gene'' (1976) Oxford:Oxford University Press. Other philosophers, however, adopt a non-physicalist position which challenges the notion that the mind is a purely physical construct. * ''Reductive physicalists'' assert that all mental states and properties will eventually be explained by scientific accounts of physiological processes and states. * ''Non-reductive physicalists'' argue that although the brain is all there ''is'' to the mind, the predicates and vocabulary used in mental descriptions and explanations are indispensable, and cannot be reduced to the language and lower-level explanations of physical science.Putnam, Hilary (1967). "Psychological Predicates", in W.H. Capitan and D.D. Merrill, eds., ''Art, Mind and Religion'' Pittsburgh: University of Pittsburgh Press. Continued progress in neuroscience has helped to clarify many of these issues, and its findings have been taken by many to support physicalists' assertions. Nevertheless, our knowledge is incomplete, and modern philosophers of mind continue to discuss how subjective qualia and the intentional mental states can be naturally explained. There is also the problem of Quantum Mechanics, whose Copenhagen interpretation can be understood as a form of
perspectivism Perspectivism (german: Perspektivismus; also called perspectivalism) is the epistemological principle that perception of and knowledge of something are always bound to the interpretive perspectives of those observing it. While perspectivism reg ...
. As the Copenhagen interpretation is not universally accepted, an exact mechanism of the
collapse of the wavefunction In quantum mechanics, wave function collapse occurs when a wave function—initially in a superposition of several eigenstates—reduces to a single eigenstate due to interaction with the external world. This interaction is called an ''observat ...
remains elusive, and the role of mind in fundamental physical theory is unclear.


Scientific study


Neuroscience

Neuroscience studies the nervous system, the physical basis of the mind. At the systems level, neuroscientists investigate how
biological neural networks A neural circuit is a population of neurons interconnected by synapses to carry out a specific function when activated. Neural circuits interconnect to one another to form large scale brain networks. Biological neural networks have inspired t ...
form and physiologically interact to produce mental functions and content such as
reflex In biology, a reflex, or reflex action, is an involuntary, unplanned sequence or action and nearly instantaneous response to a stimulus. Reflexes are found with varying levels of complexity in organisms with a nervous system. A reflex occurs ...
es, multisensory integration,
motor coordination Motor coordination is the orchestrated movement of multiple body parts as required to accomplish intended actions, like walking. This coordination is achieved by adjusting kinematic and kinetic parameters associated with each body part involved in t ...
,
circadian rhythm A circadian rhythm (), or circadian cycle, is a natural, internal process that regulates the sleep–wake cycle and repeats roughly every 24 hours. It can refer to any process that originates within an organism (i.e., Endogeny (biology), endogeno ...
s, emotional responses,
learning Learning is the process of acquiring new understanding, knowledge, behaviors, skills, value (personal and cultural), values, attitudes, and preferences. The ability to learn is possessed by humans, animals, and some machine learning, machines ...
, and memory. The underlying physical basis of
learning Learning is the process of acquiring new understanding, knowledge, behaviors, skills, value (personal and cultural), values, attitudes, and preferences. The ability to learn is possessed by humans, animals, and some machine learning, machines ...
and memory is likely dynamic changes in
gene expression Gene expression is the process by which information from a gene is used in the synthesis of a functional gene product that enables it to produce end products, protein or non-coding RNA, and ultimately affect a phenotype, as the final effect. The ...
that occur in brain
neurons A neuron, neurone, or nerve cell is an electrically excitable cell that communicates with other cells via specialized connections called synapses. The neuron is the main component of nervous tissue in all animals except sponges and placozoa. N ...
. Such expression changes are introduced by
epigenetic In biology, epigenetics is the study of stable phenotypic changes (known as ''marks'') that do not involve alterations in the DNA sequence. The Greek prefix '' epi-'' ( "over, outside of, around") in ''epigenetics'' implies features that are "o ...
mechanisms.
Epigenetic In biology, epigenetics is the study of stable phenotypic changes (known as ''marks'') that do not involve alterations in the DNA sequence. The Greek prefix '' epi-'' ( "over, outside of, around") in ''epigenetics'' implies features that are "o ...
regulation of gene expression ordinarily involves chemical modification of DNA or DNA-associated histone proteins. Such chemical modifications can cause long-lasting changes in gene expression. Epigenetic mechanisms employed in learning and memory include the DNMT3A promoted
methylation In the chemical sciences, methylation denotes the addition of a methyl group on a substrate, or the substitution of an atom (or group) by a methyl group. Methylation is a form of alkylation, with a methyl group replacing a hydrogen atom. These t ...
and
TET Tet or TET may refer to: Vietnam *Tết or Tết Nguyên Đán, the Vietnamese new year, Lunar new year *Tet Offensive, a military campaign during the Vietnam War that began in 1968 **Tet 1969 Geography *Têt (river) in Roussillon, France *Tét, ...
promoted demethylation of neuronal DNA as well as
methylation In the chemical sciences, methylation denotes the addition of a methyl group on a substrate, or the substitution of an atom (or group) by a methyl group. Methylation is a form of alkylation, with a methyl group replacing a hydrogen atom. These t ...
, acetylation and deacetylation of neuronal histone proteins. Also, long term excitation of neural pathways and subsequent endocrinal signaling, can provide a capacity for structural activation of
gene expression Gene expression is the process by which information from a gene is used in the synthesis of a functional gene product that enables it to produce end products, protein or non-coding RNA, and ultimately affect a phenotype, as the final effect. The ...
in the
histone code The histone code is a hypothesis that the transcription of genetic information encoded in DNA is in part regulated by chemical modifications (known as ''histone marks'') to histone proteins, primarily on their unstructured ends. Together with sim ...
; allowing a potential mechanism of throughput epigenetic interaction with the nervous system. At a larger scale, efforts in computational neuroscience have developed large-scale models that simulate simple, functioning brains. As of 2012, such models include the thalamus, basal ganglia, prefrontal cortex, motor cortex, and occipital cortex, and consequentially simulated brains can learn, respond to visual stimuli, coordinate motor responses, form short-term memories, and learn to respond to patterns. Currently, researchers aim to program the hippocampus and
limbic system The limbic system, also known as the paleomammalian cortex, is a set of brain structures located on both sides of the thalamus, immediately beneath the medial temporal lobe of the cerebrum primarily in the forebrain.Schacter, Daniel L. 2012. ''Ps ...
, hypothetically imbuing the simulated mind with long-term memory and crude emotions. By contrast, affective neuroscience studies the neural mechanisms of personality, emotion, and mood primarily through experimental tasks.


Cognitive science

Cognitive science examines the mental functions that give rise to
information processing Information processing is the change (processing) of information in any manner detectable by an observer. As such, it is a process that ''describes'' everything that happens (changes) in the universe, from the falling of a rock (a change in posit ...
, termed
cognition Cognition refers to "the mental action or process of acquiring knowledge and understanding through thought, experience, and the senses". It encompasses all aspects of intellectual functions and processes such as: perception, attention, thought, ...
. These include perception,
attention Attention is the behavioral and cognitive process of selectively concentrating on a discrete aspect of information, whether considered subjective or objective, while ignoring other perceivable information. William James (1890) wrote that "Atte ...
, working memory, long-term memory, producing and understanding language,
learning Learning is the process of acquiring new understanding, knowledge, behaviors, skills, value (personal and cultural), values, attitudes, and preferences. The ability to learn is possessed by humans, animals, and some machine learning, machines ...
, reasoning,
problem solving Problem solving is the process of achieving a goal by overcoming obstacles, a frequent part of most activities. Problems in need of solutions range from simple personal tasks (e.g. how to turn on an appliance) to complex issues in business an ...
, and
decision making In psychology, decision-making (also spelled decision making and decisionmaking) is regarded as the cognitive process resulting in the selection of a belief or a course of action among several possible alternative options. It could be either rati ...
. Cognitive science seeks to understand thinking "in terms of representational structures in the mind and computational procedures that operate on those structures".Thagard, Paul
Cognitive Science
, The Stanford Encyclopedia of Philosophy (Fall 2008 Edition), Edward N. Zalta (ed.).
At the birth of cognitive science in the 1960s and 1970s, the paradigm of the computational theory of mind was widely adopted. This paradigm holds that the mind is essentially a computational system, and its explanation needs to be provided in terms of a ''computational description''. More recently, rival paradigms gained ground within cognitive science, namely the ''neurophysical description'' and the ''intentional description''. Though the interface between neuroscience and an exact model of
cognition Cognition refers to "the mental action or process of acquiring knowledge and understanding through thought, experience, and the senses". It encompasses all aspects of intellectual functions and processes such as: perception, attention, thought, ...
is not yet made, progress in biological neuron models help to mathematically quantify cognitive neuroscience; and elaborate a theory of mind that can be provable. However a theoretically fundamental synthesis in psychology, cognitive science, neuroscience, and biophysics must be made; for the problem of mind and its faculties to gain tractable scientific ground. Over the past years, research in cognitive sciences has highlighted the importance of the body for cognition. Proponents of the embodied cognition theory of mind hold that cognition (and mental phenomena) is the product of active interactions between individuals and their surrounding environment.


Psychology

Psychology is the scientific study of human behavior, mental functioning, and experience. As both an academic and applied discipline, Psychology involves the
scientific study Scientific study is a kind of study that involves scientific theory, scientific models, experiments and physical situations. It may refer to: *Scientific method, a body of techniques for investigating phenomena, based on empirical or measurabl ...
of mental processes such as perception,
cognition Cognition refers to "the mental action or process of acquiring knowledge and understanding through thought, experience, and the senses". It encompasses all aspects of intellectual functions and processes such as: perception, attention, thought, ...
, emotion, personality, as well as environmental influences, such as social and cultural influences, and interpersonal relationships, in order to devise theories of human behavior. Psychological patterns can be understood as low cost ways of information processing. Psychology also refers to the application of such knowledge to various spheres of human activity, including problems of individuals' daily lives and the treatment of mental health problems. Psychology differs from the other social sciences (e.g. anthropology, economics, political science, and sociology) due to its focus on experimentation at the scale of the individual, or individuals in small groups as opposed to large groups,
institutions Institutions are humanly devised structures of rules and norms that shape and constrain individual behavior. All definitions of institutions generally entail that there is a level of persistence and continuity. Laws, rules, social conventions a ...
or societies. Historically, psychology differed from biology and neuroscience in that it was primarily concerned with mind rather than brain. Modern psychological science incorporates
physiological Physiology (; ) is the scientific study of functions and mechanisms in a living system. As a sub-discipline of biology, physiology focuses on how organisms, organ systems, individual organs, cells, and biomolecules carry out the chemical ...
and
neurological Neurology (from el, νεῦρον (neûron), "string, nerve" and the suffix -logia, "study of") is the branch of medicine dealing with the diagnosis and treatment of all categories of conditions and disease involving the brain, the spinal ...
processes into its conceptions of perception,
cognition Cognition refers to "the mental action or process of acquiring knowledge and understanding through thought, experience, and the senses". It encompasses all aspects of intellectual functions and processes such as: perception, attention, thought, ...
, behaviour, and
mental disorders A mental disorder, also referred to as a mental illness or psychiatric disorder, is a behavioral or mental pattern that causes significant distress or impairment of personal functioning. Such features may be persistent, relapsing and remitti ...
.


Psychiatry, Neurology and Neurosurgery

Psychiatry, Neurology and Neurosurgery are the specialties within the field of Medicine that are devoted to the study of the mind and to the treatment of humans with
mental disorders A mental disorder, also referred to as a mental illness or psychiatric disorder, is a behavioral or mental pattern that causes significant distress or impairment of personal functioning. Such features may be persistent, relapsing and remitti ...
and other medical conditions affecting the mind and nervous system. Psychiatrists, Neurologists and Neurosurgeons conduct research in clinical, academic and industry settings.


Mental health

By analogy with the health of the body, one can speak metaphorically of a state of health of the mind, or mental health.
Merriam-Webster Merriam-Webster, Inc. is an American company that publishes reference books and is especially known for its dictionaries. It is the oldest dictionary publisher in the United States. In 1831, George and Charles Merriam founded the company as ...
defines mental health as "a state of emotional and psychological well-being in which an individual is able to use his or her cognitive and emotional capabilities, function in society, and meet the ordinary demands of everyday life". According to the World Health Organization (WHO), there is no one "official" definition of mental health. Cultural differences, subjective assessments, and competing professional theories all affect how "mental health" is defined. In general, most experts agree that "mental health" and " mental disorder" are not opposites. In other words, the absence of a recognized mental disorder is not necessarily an indicator of mental health. One way to think about mental health is by looking at how effectively and successfully a person functions. Feeling capable and competent; being able to handle normal levels of stress, maintaining satisfying relationships, and leading an independent life; and being able to "bounce back" or recover from difficult situations, are all signs of mental health.
Psychotherapy Psychotherapy (also psychological therapy, talk therapy, or talking therapy) is the use of psychological methods, particularly when based on regular personal interaction, to help a person change behavior, increase happiness, and overcome pro ...
is an
interpersonal The concept of interpersonal relationship involves social associations, connections, or affiliations between two or more people. Interpersonal relationships vary in their degree of intimacy or self-disclosure, but also in their duration, in t ...
, relational intervention used by trained psychotherapists to aid clients in problems of living. This usually includes increasing individual sense of well-being and reducing subjective discomforting experience. Psychotherapists employ a range of techniques based on experiential relationship building,
dialogue Dialogue (sometimes spelled dialog in American English) is a written or spoken conversational exchange between two or more people, and a literary and theatrical form that depicts such an exchange. As a philosophical or didactic device, it is c ...
, communication and
behavior Behavior (American English) or behaviour (British English) is the range of actions and mannerisms made by individuals, organisms, systems or artificial entities in some environment. These systems can include other systems or organisms as wel ...
change and that are designed to improve the mental health of a client or patient, or to improve group relationships (such as in a family). Most forms of psychotherapy use only spoken
conversation Conversation is interactive communication between two or more people. The development of conversational skills and etiquette is an important part of socialization. The development of conversational skills in a new language is a frequent focus ...
, though some also use various other forms of communication such as the written word, art, drama, narrative story, or therapeutic touch. Psychotherapy occurs within a structured encounter between a trained therapist and client(s). Purposeful, theoretically based psychotherapy began in the 19th century with psychoanalysis; since then, scores of other approaches have been developed and continue to be created.


Non-human


Animal cognition

Animal cognition, or cognitive ethology, is the title given to a modern approach to the mental capacities of animals. It has developed out of
comparative psychology Comparative psychology refers to the scientific study of the behavior and mental processes of non-human animals, especially as these relate to the phylogenetic history, adaptive significance, and development of behavior. Research in this area addr ...
, but has also been strongly influenced by the approach of ethology,
behavioral ecology Behavioral ecology, also spelled behavioural ecology, is the study of the evolutionary basis for animal behavior due to ecological pressures. Behavioral ecology emerged from ethology after Niko Tinbergen outlined four questions to address when ...
, and evolutionary psychology. Much of what used to be considered under the title of "animal intelligence" is now thought of under this heading. Animal language acquisition, attempting to discern or understand the degree to which animal cognition can be revealed by linguistics-related study, has been controversial among cognitive linguists.


Artificial intelligence

In 1950
Alan M. Turing Alan Mathison Turing (; 23 June 1912 – 7 June 1954) was an English mathematician, computer scientist, logician, cryptanalyst, philosopher, and theoretical biologist. Turing was highly influential in the development of theoretical comp ...
published "Computing machinery and intelligence" in ''
Mind The mind is the set of faculties responsible for all mental phenomena. Often the term is also identified with the phenomena themselves. These faculties include thought, imagination, memory, will, and sensation. They are responsible for various m ...
'', in which he proposed that machines could be tested for intelligence using questions and answers. This process is now named the Turing Test. The term Artificial Intelligence (AI) was first used by John McCarthy who considered it to mean "the science and engineering of making intelligent machines". It can also refer to intelligence as exhibited by an artificial (''man-made'', ''non-natural'', ''manufactured'') entity. AI is studied in overlapping fields of computer science, psychology, neuroscience and engineering, dealing with intelligent
behavior Behavior (American English) or behaviour (British English) is the range of actions and mannerisms made by individuals, organisms, systems or artificial entities in some environment. These systems can include other systems or organisms as wel ...
,
learn Learning is the process of acquiring new understanding, knowledge, behaviors, skills, values, attitudes, and preferences. The ability to learn is possessed by humans, animals, and some machines; there is also evidence for some kind of learnin ...
ing and
adaptation In biology, adaptation has three related meanings. Firstly, it is the dynamic evolutionary process of natural selection that fits organisms to their environment, enhancing their evolutionary fitness. Secondly, it is a state reached by the po ...
and usually developed using customized
machine A machine is a physical system using Power (physics), power to apply Force, forces and control Motion, movement to perform an action. The term is commonly applied to artificial devices, such as those employing engines or motors, but also to na ...
s or
computer A computer is a machine that can be programmed to Execution (computing), carry out sequences of arithmetic or logical operations (computation) automatically. Modern digital electronic computers can perform generic sets of operations known as C ...
s. Research in AI is concerned with producing machines to automate tasks requiring intelligent behavior. Examples include
control Control may refer to: Basic meanings Economics and business * Control (management), an element of management * Control, an element of management accounting * Comptroller (or controller), a senior financial officer in an organization * Controlling ...
, planning and scheduling, the ability to answer diagnostic and consumer questions,
handwriting Handwriting is the writing done with a writing instrument, such as a pen or pencil, in the hand. Handwriting includes both printing and cursive styles and is separate from formal calligraphy or typeface A typeface (or font family) is ...
,
natural language In neuropsychology, linguistics, and philosophy of language, a natural language or ordinary language is any language that has evolved naturally in humans through use and repetition without conscious planning or premeditation. Natural languages ...
,
speech Speech is a human vocal communication using language. Each language uses Phonetics, phonetic combinations of vowel and consonant sounds that form the sound of its words (that is, all English words sound different from all French words, even if ...
and
facial recognition Facial recognition or face recognition may refer to: * Face detection, often a step done before facial recognition * Face perception, the process by which the human brain understands and interprets the face * Pareidolia, which involves, in part, se ...
. As such, the study of AI has also become an engineering discipline, focused on providing solutions to real life problems, knowledge mining, software applications, strategy games like
computer chess Computer chess includes both hardware (dedicated computers) and software capable of playing chess. Computer chess provides opportunities for players to practice even in the absence of human opponents, and also provides opportunities for analysi ...
and other video games. One of the biggest limitations of AI is in the domain of actual machine comprehension. Consequentially natural-language understanding and connectionism (where behavior of neural networks is investigated) are areas of active research and development. The debate about the nature of the mind is relevant to the development of artificial intelligence. If the mind is indeed a thing separate from or higher than the functioning of the brain, then hypothetically it would be much more difficult to recreate within a machine, if it were possible at all. If, on the other hand, the mind is no more than the aggregated functions of the brain, then it will be possible to create a machine with a recognisable mind (though possibly only with computers much different from today's), by simple virtue of the fact that such a machine already exists in the form of the human brain.


Religion

Many religions associate spiritual qualities to the human mind. These are often tightly connected to their mythology and ideas of
afterlife The afterlife (also referred to as life after death) is a purported existence in which the essential part of an individual's identity or their stream of consciousness continues to live after the death of their physical body. The surviving ess ...
. The Indian
philosopher A philosopher is a person who practices or investigates philosophy. The term ''philosopher'' comes from the grc, φιλόσοφος, , translit=philosophos, meaning 'lover of wisdom'. The coining of the term has been attributed to the Greek th ...
-sage
Sri Aurobindo Sri Aurobindo (born Aurobindo Ghose; 15 August 1872 – 5 December 1950) was an Indian philosopher, yogi, maharishi, poet, and Indian nationalist. He was also a journalist, editing newspapers such as ''Vande Mataram''. He joined the ...
attempted to unite the Eastern and Western psychological traditions with his
integral psychology Integral theory is a synthetic metatheory developed by Ken Wilber. It attempts to place a wide diversity of theories and models into one single framework. The basis is a "spectrum of consciousness," from archaic consciousness to Absolute (philo ...
, as have many philosophers and New religious movements. Judaism teaches that "moach shalit al halev", the mind rules the heart; humans can approach the Divine intellectually, through learning and behaving according to the Divine Will as enclothed in the Torah, and use that deep logical understanding to elicit and guide emotional arousal during prayer. Christianity has tended to see the mind (Greek ''
nous ''Nous'', or Greek νοῦς (, ), sometimes equated to intellect or intelligence, is a concept from classical philosophy for the faculty of the human mind necessary for understanding what is true or real. Alternative English terms used in p ...
'') as distinct from the soul (Greek ''
psuche In psychology, the psyche is the totality of the human mind, conscious and unconscious. Many thinkers, including Carl Jung, also include in this definition the overlap and tension between the personal and the collective elements in man. Psycho ...
'') and sometimes further distinguished the spirit (Greek '' pneuma''). Western esoteric traditions sometimes refer to a
mental body The mental body (the mind) is one of the subtle bodies in esoteric philosophies, in some religious teachings and in New Age thought. It is understood as a sort of body made up of thoughts, just as the emotional body consists of emotions and the p ...
that exists on a plane other than the physical. Hinduism's various philosophical schools have debated whether the human soul (Sanskrit ''
atman Atman or Ātman may refer to: Film * ''Ātman'' (1975 film), a Japanese experimental short film directed by Toshio Matsumoto * ''Atman'' (1997 film), a documentary film directed by Pirjo Honkasalo People * Pavel Atman (born 1987), Russian hand ...
'') is distinct from, or identical to, '' Brahman'', the divine reality. Taoism sees the human being as contiguous with natural forces, and the mind as not separate from the
body Body may refer to: In science * Physical body, an object in physics that represents a large amount, has mass or takes up space * Body (biology), the physical material of an organism * Body plan, the physical features shared by a group of anima ...
. Confucianism sees the mind, like the body, as inherently perfectible.


Buddhism

Buddhist teachings explain the moment-to-moment manifestation of the mind-stream. The components that make up the mind are known as the five aggregates (i.e., material form, feelings, perception, volition, and sensory consciousness), which arise and pass away continuously. The arising and passing of these aggregates in the present moment is described as being influenced by five causal laws: biological laws, psychological laws, physical laws, volitional laws, and universal laws. The Buddhist practice of
mindfulness Mindfulness is the practice of purposely bringing one's attention to the present-moment experience without evaluation, a skill one develops through meditation or other training. Mindfulness derives from ''sati'', a significant element of Hind ...
involves attending to this constantly changing mind-stream. According to Buddhist philosopher Dharmakirti, the mind has two fundamental qualities: "clarity and cognizes". If something is not those two qualities, it cannot validly be called mind. "Clarity" refers to the fact that mind has no color, shape, size, location, weight, or any other physical characteristic, and "cognizes" that it functions to know or perceive objects. "Knowing" refers to the fact that mind is aware of the contents of experience, and that, in order to exist, mind must be cognizing an object. You cannot have a mind – whose function is to cognize an object – existing without cognizing an object. Mind, in Buddhism, is also described as being "space-like" and "illusion-like". Mind is space-like in the sense that it is not physically obstructive. It has no qualities which would prevent it from existing. In Mahayana Buddhism, mind is illusion-like in the sense that it is empty of inherent existence. This does not mean it does not exist, it means that it exists in a manner that is counter to our ordinary way of misperceiving how phenomena exist, according to Buddhism. When the mind is itself cognized properly, without misperceiving its mode of existence, it appears to exist like an illusion. There is a big difference however between being "space and illusion" and being "space-like" and "illusion-like". Mind is not composed of space, it just shares some descriptive similarities to space. Mind is not an illusion, it just shares some descriptive qualities with illusions. Buddhism posits that there is no inherent, unchanging identity (Inherent I, Inherent Me) or phenomena (Ultimate self, inherent self, Atman, Soul, Self-essence, Jiva, Ishvara, humanness essence, etc.) which is the experiencer of our experiences and the agent of our actions. In other words, human beings consist of merely a body and a mind, and nothing extra. Within the body there is no part or set of parts which is – by itself or themselves – the person. Similarly, within the mind there is no part or set of parts which are themselves "the person". A human being merely consists of five aggregates, or ''
skandha (Sanskrit) or (Pāḷi) means "heaps, aggregates, collections, groupings". In Buddhism, it refers to the five aggregates of clinging (), the five material and mental factors that take part in the rise of craving and clinging. They are also ...
s'' and nothing else. In the same way, "mind" is what can be validly conceptually labelled onto our mere experience of clarity and knowing. There is something separate and apart from clarity and knowing which is "Awareness", in Buddhism. "Mind" is that part of experience the sixth sense door, which can be validly referred to as mind by the concept-term "mind". There is also not "objects out there, mind in here, and experience somewhere in-between". There is a third thing called "awareness" which exists being aware of the contents of mind and what mind cognizes. There are five senses (arising of mere experience: shapes, colors, the components of smell, components of taste, components of sound, components of touch) and mind as the sixth institution; this means, expressly, that there can be a third thing called "awareness" and a third thing called "experiencer who is aware of the experience". This awareness is deeply related to "no-self" because it does not judge the experience with craving or aversion. Clearly, the experience arises and is known by mind, but there is a third thing calls Sati what is the "real experiencer of the experience" that sits apart from the experience and which can be aware of the experience in 4 levels. (Maha Sathipatthana Sutta.) # Body # Sensations (Changes of the body mind.) # Mind, # Contents of the mind. (Changes of the body mind.) To be aware of these four levels one needs to cultivate equanimity toward Craving and Aversion. This is Called Vipassana which is different from the way of reacting with Craving and Aversion. This is the state of being aware and equanimous to the complete experience of here and now. This is the way of Buddhism, with regards to mind and the ultimate nature of minds (and persons).


Mortality

Due to the mind–body problem, a lot of interest and debate surrounds the question of what happens to one's conscious mind as one's body dies. During
brain death Brain death is the permanent, irreversible, and complete loss of brain function which may include cessation of involuntary activity necessary to sustain life. It differs from persistent vegetative state, in which the person is alive and some aut ...
all brain function permanently ceases. According to some neuroscientific views which see these processes as the physical basis of mental phenomena, the mind fails to survive brain death and ceases to exist. This permanent loss of consciousness after death is sometimes called " eternal oblivion". The belief that some spiritual or
incorporeal Incorporeality is "the state or quality of being incorporeal or bodiless; immateriality; incorporealism." Incorporeal (Greek: ἀσώματος) means "Not composed of matter; having no material existence." Incorporeality is a quality of souls, s ...
component ( soul) exists and that it is preserved after death is described by the term "
afterlife The afterlife (also referred to as life after death) is a purported existence in which the essential part of an individual's identity or their stream of consciousness continues to live after the death of their physical body. The surviving ess ...
".


Parapsychology

Parapsychology is the study of certain types of paranormal phenomena, or of phenomena which appear to be paranormal or not have any scientific basis, such as precognition, telekinesis and
telepathy Telepathy () is the purported vicarious transmission of information from one person's mind to another's without using any known human sensory channels or physical interaction. The term was first coined in 1882 by the classical scholar Frederic W ...
. The term is based on the Greek ''para'' ('beside, beyond'), ''psyche'' ('soul, mind'), and '' logos'' ('account, explanation') and was coined by psychologist Max Dessoir in or before 1889.
J.B. Rhine Joseph Banks Rhine (September 29, 1895 – February 20, 1980), usually known as J. B. Rhine, was an American botanist who founded parapsychology as a branch of psychology, founding the parapsychology lab at Duke University, the ''Journ ...
tried to popularize "parapsychology" using fraudulent techniques as a replacement for the earlier term "psychical research", during a shift in methodologies which brought experimental methods to the study of psychic phenomena.Encyclopedia of Occultism & Parapsychology edited by J. Gordon Melton Gale Research, Parapsychology is not accepted among the scientific community as science, as psychic abilities have not been demonstrated to exist. The status of parapsychology as a science has also been disputed, with many scientists regarding the discipline as pseudoscience.


See also

* Outline of human intelligence – topic tree presenting the traits, capacities, models, and research fields of human intelligence, and more. * Outline of thought – topic tree that identifies many types of thoughts, types of thinking, aspects of thought, related fields, and more. *
Embodied cognition Embodied cognition is the theory that many features of cognition, whether human or otherwise, are shaped by aspects of an organism's entire body. Sensory and motor systems are seen as fundamentally integrated with cognitive processing. The cognit ...


References


Further reading

* Max Bertolero and
Danielle S. Bassett Dani Smith Bassett (born ) is an American physicist and systems neuroscientist who was the youngest individual to be awarded a 2014 MacArthur fellowship. Bassett, whose pronouns are they/them, was also awarded a 2014 Sloan fellowship. They are ...
, "How Matter Becomes Mind: The new discipline of network neuroscience yields a picture of how mental activity arises from carefully orchestrated interactions among different brain areas", '' Scientific American'', vol. 321, no. 1 (July 2019), pp. 26–33. *


External links

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