Psychology is the science of behavior and mind. Psychology includes the study of conscious and unconscious phenomena, as well as feeling and thought, it is an academic discipline of immense scope. Psychologists seek an understanding of the emergent properties of brains, all the variety of phenomena linked to those emergent properties; as a social science it aims to understand individuals and groups by establishing general principles and researching specific cases. In this field, a professional practitioner or researcher is called a psychologist and can be classified as a social, behavioral, or cognitive scientist. Psychologists attempt to understand the role of mental functions in individual and social behavior, while exploring the physiological and biological processes that underlie cognitive functions and behaviors. Psychologists explore behavior and mental processes, including perception, attention, intelligence, motivation, brain functioning, personality; this extends to interaction between people, such as interpersonal relationships, including psychological resilience, family resilience, other areas.
Psychologists of diverse orientations consider the unconscious mind. Psychologists employ empirical methods to infer causal and correlational relationships between psychosocial variables. In addition, or in opposition, to employing empirical and deductive methods, some—especially clinical and counseling psychologists—at times rely upon symbolic interpretation and other inductive techniques. Psychology has been described as a "hub science" in that medicine tends to draw psychological research via neurology and psychiatry, whereas social sciences most draws directly from sub-disciplines within psychology. While psychological knowledge is applied to the assessment and treatment of mental health problems, it is directed towards understanding and solving problems in several spheres of human activity. By many accounts psychology aims to benefit society; the majority of psychologists are involved in some kind of therapeutic role, practicing in clinical, counseling, or school settings. Many do scientific research on a wide range of topics related to mental processes and behavior, work in university psychology departments or teach in other academic settings.
Some are employed in industrial and organizational settings, or in other areas such as human development and aging, sports and the media, as well as in forensic investigation and other aspects of law. The word psychology derives from Greek roots meaning study of soul; the Latin word psychologia was first used by the Croatian humanist and Latinist Marko Marulić in his book, Psichiologia de ratione animae humanae in the late 15th century or early 16th century. The earliest known reference to the word psychology in English was by Steven Blankaart in 1694 in The Physical Dictionary which refers to "Anatomy, which treats the Body, Psychology, which treats of the Soul."In 1890, William James defined psychology as "the science of mental life, both of its phenomena and their conditions". This definition enjoyed widespread currency for decades. However, this meaning was contested, notably by radical behaviorists such as John B. Watson, who in his 1913 manifesto defined the discipline of psychology as the acquisition of information useful to the control of behavior.
Since James defined it, the term more connotes techniques of scientific experimentation. Folk psychology refers to the understanding of ordinary people, as contrasted with that of psychology professionals; the ancient civilizations of Egypt, China and Persia all engaged in the philosophical study of psychology. In Ancient Egypt the Ebers Papyrus mentioned thought disorders. Historians note that Greek philosophers, including Thales and Aristotle, addressed the workings of the mind; as early as the 4th century BC, Greek physician Hippocrates theorized that mental disorders had physical rather than supernatural causes. In China, psychological understanding grew from the philosophical works of Laozi and Confucius, from the doctrines of Buddhism; this body of knowledge involves insights drawn from introspection and observation, as well as techniques for focused thinking and acting. It frames the universe as a division of, interaction between, physical reality and mental reality, with an emphasis on purifying the mind in order to increase virtue and power.
An ancient text known as The Yellow Emperor's Classic of Internal Medicine identifies the brain as the nexus of wisdom and sensation, includes theories of personality based on yin–yang balance, analyzes mental disorder in terms of physiological and social disequilibria. Chinese scholarship focused on the brain advanced in the Qing Dynasty with the work of Western-educated Fang Yizhi, Liu Zhi, Wang Qingren. Wang Qingren emphasized the importance of the brain as the center of the nervous system, linked mental disorder with brain diseases, investigated the causes of dreams and insomnia, advanced a theory of hemispheric lateralization in brain function. Distinctions in types of awareness appear in the ancient thought of India, influenced by Hinduism. A central idea of the Upanishads is the distinction between a person's transient mundane self and their eternal unchanging soul. Divergent Hindu doctrines, Buddhism, have challenged this hierarchy of selves, but have all emphasized the importance of reaching higher
Psychology of religion
Speaking, psychology of religion consists of the application of psychological methods and interpretive frameworks to the diverse contents of religious traditions as well as to both religious and irreligious individuals. The extraordinary range of methods and frameworks can be helpfully summed up regarding the classic distinction between the natural-scientific and human-scientific approaches: the first cluster proceeds by means of objective and preferably experimental procedures for testing hypotheses regarding the causal connections among the objects of one's study. In contrast, the human-scientific approach accesses the human world of experience using qualitative and interpretive methods, with the goal of discerning meaningful rather than causal connections among the phenomena one seeks to understand. Psychologists of religion pursue three major projects: systematic description of religious contents, attitudes and expressions; the psychology of religion first arose as a self-conscious discipline in the late 19th century, but all three of these tasks have a history going back many centuries before that.
The challenge for the psychology of religion is threefold: to provide a thoroughgoing description of the objects of investigation, whether they be shared religious content or individual experiences, attitudes, or conduct. These fruits may be both negative; the first, descriptive task requires a clarification of one's terms—above all, the word religion. Historians of religion have long underscored the problematic character of this term, noting that its usage over the centuries has changed in significant ways in the direction of reification; the early psychologists of religion were aware of these difficulties acknowledging that the definitions they were choosing to use were to some degree arbitrary. With the rise of positivistic trends in psychology over the course of the 20th century the demand that all phenomena be operationalized by quantitative procedures, psychologists of religion developed a multitude of scales, most of them developed for use with Protestant Christians. Factor analysis was brought into play by both psychologists and sociologists of religion, to establish a fixed core of dimensions and a corresponding set of scales.
The justification and adequacy of these efforts in the light of constructivist and other postmodern viewpoints, remains a matter of debate. In the last several decades among clinical psychologists, a preference for the terms "spirituality" and "spiritual" has emerged, along with efforts to distinguish them from "religion" and "religious." In the United States, "religion" has for many become associated with sectarian institutions and their obligatory creeds and rituals, thus giving the word a negative cast. In fact, "spirituality" has undergone an evolution in the West, from a time when it was a synonym for religion in its original, subjective meaning. Today, efforts are ongoing to "operationalize" these terms, with little regard for their history in their Western context, with the apparent realist assumption that underlying them are fixed qualities identifiable using empirical procedures. Schnitker and Emmons theorized that the understanding of religion as a search for meaning makes implications in the three psychological areas of motivation and social relationships.
The cognitive aspects relate to God and a sense of purpose, the motivational ones to the need to control, the religious search for meaning is weaved into social communities. American psychologist and philosopher William James is regarded by most psychologists of religion as the founder of the field, he served as president of the American Psychological Association, wrote one of the first psychology textbooks. In the psychology of religion, James' influence endures, his Varieties of Religious Experience is considered to be the classic work in the field, references to James' ideas are common at professional conferences. James distinguished between personal religion. Institutional religion refers to the religious group or organization and plays an important part in a society's culture. Personal religion, in which the individual has mystical experience, can be experienced regardless of the culture. James was most interested in understanding personal religious experience. In studying personal religious experiences, James made a distinction between healthy-minded and sick-souled religiousness.
Individuals predisposed to healthy-mindedness tend to ignore the evil in the world and focus on the positive and the good. James used examples of Walt Whitman and the "mind-cure" religious movement to illustrate healthy-mindedness in The Varieties of Religious Experience. In contrast, individuals predisposed to having a sick-souled religion are unable to ignore evil and suffering and need a unifying experience, religious or otherwise, to reconcile good and evil. James included quotations from Leo Tolstoy and John Bunyan
Human factors and ergonomics
Human factors and ergonomics is the application of psychological and physiological principles to the design of products and systems. The goal of human factors is to reduce human error, increase productivity, enhance safety and comfort with a specific focus on the interaction between the human and the thing of interest, it is not changes or amendments to the work enviornment but encompases theory, methods and principles all applied in the field of ergonomics. The field is a combination of numerous disciplines, such as psychology, engineering, industrial design, anthropometry, interaction design, visual design, user experience, user interface design. In research, human factors employs the scientific method to study human behavior so that the resultant data may be applied to the four primary goals. In essence, it is the study of designing equipment and processes that fit the human body and its cognitive abilities; the two terms "human factors" and "ergonomics" are synonymous. The International Ergonomics Association defines ergonomics or human factors as follows: Ergonomics is the scientific discipline concerned with the understanding of interactions among humans and other elements of a system, the profession that applies theory, principles and methods to design to optimize human well-being and overall system performance.
Human factors is employed to fulfill the goals of occupational safety and productivity. It is relevant in the design of such things as safe furniture and easy-to-use interfaces to machines and equipment. Proper ergonomic design is necessary to prevent repetitive strain injuries and other musculoskeletal disorders, which can develop over time and can lead to long-term disability. Human factors and ergonomics is concerned with the "fit" between the user and environment or "fitting a person to a job", it accounts for the user's capabilities and limitations in seeking to ensure that tasks, functions and the environment suit that user. To assess the fit between a person and the used technology, human factors specialists or ergonomists consider the job being done and the demands on the user. Ergonomics draws on many disciplines in its study of humans and their environments, including anthropometry, mechanical engineering, industrial engineering, industrial design, information design, physiology, cognitive psychology and organizational psychology, space psychology.
The term ergonomics first entered the modern lexicon when Polish scientist Wojciech Jastrzębowski used the word in his 1857 article Rys ergonomji czyli nauki o pracy, opartej na prawdach poczerpniętych z Nauki Przyrody. The French scholar Jean-Gustave Courcelle-Seneuil without knowledge of Jastrzębowski's article, used the word with a different meaning in 1858; the introduction of the term to the English lexicon is attributed to British psychologist Hywel Murrell, at the 1949 meeting at the UK's Admiralty, which led to the foundation of The Ergonomics Society. He used it to encompass the studies in which he had been engaged during and after World War II; the expression human factors is a predominantly North American term, adopted to emphasize the application of the same methods to non-work-related situations. A "human factor" is a physical or cognitive property of an individual or social behavior specific to humans that may influence the functioning of technological systems; the terms "human factors" and "ergonomics" are synonymous.
Ergonomics comprise three main fields of research: physical and organizational ergonomics. There are many specializations within these broad categories. Specializations in the field of physical ergonomics may include visual ergonomics. Specializations within the field of cognitive ergonomics may include usability, human–computer interaction, user experience engineering; some specializations may cut across these domains: Environmental ergonomics is concerned with human interaction with the environment as characterized by climate, pressure, light. The emerging field of human factors in highway safety uses human factor principles to understand the actions and capabilities of road users – car and truck drivers, cyclists, etc. – and use this knowledge to design roads and streets to reduce traffic collisions. Driver error is listed as a contributing factor in 44% of fatal collisions in the United States, so a topic of particular interest is how road users gather and process information about the road and its environment, how to assist them to make the appropriate decision.
New terms are being generated all the time. For instance, "user trial engineer" may refer to a human factors professional who specializes in user trials. Although the names change, human factors professionals apply an understanding of human factors to the design of equipment and working methods to improve comfort, health and productivity. According to the International Ergonomics Association, within the discipline of ergonomics there exist domains of specialization. Physical ergonomics is concerned with human anatomy, some of the anthropometric and bio mechanical characteristics as they relate to physical activity. Physical ergonomic principles have been used in the design of both consumer and indu
Social psychology is the scientific study of how people's thoughts and behaviors are influenced by the actual, imagined or implied presence of others. In this definition, scientific refers to the empirical investigation using the scientific method; the terms thoughts and behavior refer to psychological variables that can be measured in humans. The statement that others' presence may be imagined or implied suggests that humans are malleable to social influences when alone, such as when watching television or following internalized cultural norms. Social psychologists explain human behavior as a result of the interaction of mental states and social situations. Social psychologists examine factors that cause behaviors to unfold in a given way in the presence of others, they study conditions under which certain behavior and feelings occur. Social psychology is concerned with the way these feelings, beliefs and goals are cognitively constructed and how these mental representations, in turn, influence our interactions with others.
Social psychology traditionally bridged the gap between sociology. During the years following World War II there was frequent collaboration between psychologists and sociologists; the two disciplines, have become specialized and isolated from each other in recent years, with sociologists focusing on "macro variables" to a much greater extent than psychologists. Sociological approaches to psychology remain an important counterpart to psychological research in this area. In addition to the split between psychology and sociology, there has been a somewhat less pronounced difference in emphasis between American social psychologists and European social psychologists; as a generalization, American researchers traditionally have focused more on the individual, whereas Europeans have paid more attention to group level phenomena. Although there were some older writings about social psychology, such as those by Islamic philosopher Al-Farabi, the discipline of social psychology, as its modern-day definition, began in the United States at the beginning of the 20th century.
By that time, the discipline had developed a significant foundation. Following the 18th century, those in the emerging field of social psychology were concerned with developing concrete explanations for different aspects of human nature, they attempted to discover concrete cause and effect relationships that explained the social interactions in the world around them. In order to do so, they believed that the scientific method, an empirically based scientific measure, could be applied to human behavior; the first published study in this area was an experiment in 1898 by Norman Triplett, on the phenomenon of social facilitation. During the 1930s, many Gestalt psychologists, most notably Kurt Lewin, fled to the United States from Nazi Germany, they were instrumental in developing the field as something separate from the behavioral and psychoanalytic schools that were dominant during that time, social psychology has always maintained the legacy of their interests in perception and cognition. Attitudes and small group phenomena were the most studied topics in this era.
During World War II, social psychologists studied persuasion and propaganda for the U. S. military. After the war, researchers became interested in a variety of social problems, including gender issues and racial prejudice. Most notable and contentious of these were the Stanley Milgram shock experiments on obedience to authority. In the sixties, there was growing interest in new topics, such as cognitive dissonance, bystander intervention, aggression. By the 1970s, social psychology in America had reached a crisis. There was heated debate over the ethics of laboratory experimentation, whether or not attitudes predicted behavior, how much science could be done in a cultural context; this was the time when a radical situationist approach challenged the relevance of self and personality in psychology. Throughout the 1980s and 1990s social psychology reached a more mature level. Two of the areas social psychology matured in were methods. Careful ethical standards now regulate research. Pluralistic and multicultural perspectives have emerged.
Modern researchers are interested in many phenomena, but attribution, social cognition, the self-concept are the greatest areas of growth in recent years. Social psychologists have maintained their applied interests with contributions in the social psychology of health, education and the workplace. In social psychology, attitudes are defined as learned, global evaluations of a person, place, or issue that influence thought and action. Put more attitudes are basic expressions of approval or disapproval, favorability or unfavorability, or as Bem put it, likes and dislikes. Examples would include liking chocolate ice cream, or endorsing the values of a particular political party. Social psychologists have studied attitude formation, the structure of attitudes, attitude change, the function of attitudes, the relationship between attitudes and behavior; because people are influenced by the situation, general attitudes are not always good predictors of specific behavior. For example, for a variety of reasons, a person may value the environment but not recycle a can on a particular day.
In recent times, research on attitudes has examined the distinction between traditional, self-reported attitude measures and "implicit" or unconscious attitudes. For example, experiments using the Implicit Association Test have found that people demonstrate implicit bias against other races when their explicit responses
Cognitive psychology is the scientific study of mental processes such as "attention, language use, perception, problem solving and thinking". Much of the work derived from cognitive psychology has been integrated into various other modern disciplines such as Cognitive Science and of psychological study, including educational psychology, social psychology, personality psychology, abnormal psychology, developmental psychology and economics. Philosophically, ruminations of the human mind and its processes have been around since the times of the ancient Greeks. In 387 BCE, Plato is known to have suggested. In 1637, René Descartes posited that humans are born with innate ideas, forwarded the idea of mind-body dualism, which would come to be known as substance dualism. From that time, major debates ensued through the 19th century regarding whether human thought was experiential, or included innate knowledge; some of those involved in this debate included George Berkeley and John Locke on the side of empiricism, Immanuel Kant on the side of nativism.
With the philosophical debate continuing, the mid to late 19th century was a critical time in the development of psychology as a scientific discipline. Two discoveries that would play substantial roles in cognitive psychology were Paul Broca's discovery of the area of the brain responsible for language production, Carl Wernicke's discovery of an area thought to be responsible for comprehension of language. Both areas were subsequently formally named for their founders and disruptions of an individual's language production or comprehension due to trauma or malformation in these areas have come to be known as Broca's aphasia and Wernicke's aphasia. From the 1920s to the 1950s, the main approach to psychology was behaviorism, its adherents viewed mental events such as thoughts, ideas and consciousness as unobservables, hence outside the realm of a science of psychology. One pioneer of cognitive psychology, who worked outside the boundaries of behaviorism was Jean Piaget. From 1926 to the 1950s and into the 1980s, he studied the thoughts and intelligence of children and adults.
In the mid-20th century, three main influences arose that would inspire and shape cognitive psychology as a formal school of thought: With the development of new warfare technology during WWII, the need for a greater understanding of human performance came to prominence. Problems such as how to best train soldiers to use new technology and how to deal with matters of attention while under duress became areas of need for military personnel. Behaviorism provided little if any insight into these matters and it was the work of Donald Broadbent, integrating concepts from human performance research and the developed information theory, that forged the way in this area. Developments in computer science would lead to parallels being drawn between human thought and the computational functionality of computers, opening new areas of psychological thought. Allen Newell and Herbert Simon spent years developing the concept of artificial intelligence and worked with cognitive psychologists regarding the implications of AI.
This encouraged a conceptualization of mental functions patterned on the way that computers handled such things as memory storage and retrieval, it opened an important doorway for cognitivism. Noam Chomsky's 1959 critique of behaviorism, empiricism more initiated what would come to be known as the "cognitive revolution". Inside psychology, in criticism of behaviorism, J. S. Bruner, J. J. Goodnow & G. A. Austin wrote "a study of thinking" in 1956. In 1960, G. A. Miller, E. Galanter and K. Pribram wrote their famous "Plans and the Structure of Behavior"; the same year and Miller founded the Harvard Center for Cognitive Studies, which institutionalized the revolution and launched the field of cognitive science. Formal recognition of the field involved the establishment of research institutions such as George Mandler's Center for Human Information Processing in 1964. Mandler described the origins of cognitive psychology in a 2002 article in the Journal of the History of the Behavioral SciencesUlric Neisser put the term "cognitive psychology" into common use through his book Cognitive Psychology, published in 1967.
Neisser's definition of "cognition" illustrates the then-progressive concept of cognitive processes: The term "cognition" refers to all processes by which the sensory input is transformed, elaborated, stored and used. It is concerned with these processes when they operate in the absence of relevant stimulation, as in images and hallucinations.... Given such a sweeping definition, it is apparent that cognition is involved in everything a human being might do, but although cognitive psychology is concerned with all human activity rather than some fraction of it, the concern is from a particular point of view. Other viewpoints are legitimate and necessary. Dynamic psychology, which begins with motives rather than with sensory input, is a case in point. Instead of asking how a man's actions and experiences result from what he saw, remembered, or believed, the dynamic psychologist asks how they follow from the subject's goals, needs, or instincts; the main focus of cognitive psychologists is on the mental processes.
Those processes include, but are not limited to, the following: The psychological definition of attention is "a state of focused awareness on a subset of the available perceptual
Cultural psychology is the study of how cultures reflect and shape the psychological processes of their members. The main tenet of cultural psychology is that mind and culture are inseparable and mutually constitutive, meaning that people are shaped by their culture and their culture is shaped by them; as Richard Shweder, one of the major proponents of the field, writes, "Cultural psychology is the study of the way cultural traditions and social practices regulate and transform the human psyche, resulting less in psychic unity for humankind than in ethnic divergences in mind and emotion." Cultural psychology is confused with cross-cultural psychology. However, cultural psychology is distinct from cross-cultural psychology in that the cross-cultural psychologists use culture as a means of testing the universality of psychological processes rather than determining how local cultural practices shape psychological processes. So whereas a cross-cultural psychologist might ask whether Jean Piaget's stages of development are universal across a variety of cultures, a cultural psychologist would be interested in how the social practices of a particular set of cultures shape the development of cognitive processes in different ways.
Cultural psychology research informs several fields within psychology, including social psychology, cultural-historical psychology, developmental psychology, cognitive psychology. However, the relativist perspective of cultural psychology, through which cultural psychologists compare thought patterns and behaviors within and across cultures, tends to clash with the universal perspectives common in most fields in psychology, which seek to qualify fundamental psychological truths that are consistent across all of humanity. According to Richard Shweder, there has been repeated failure to replicate Western psychology laboratory findings in non-Western settings. Therefore, a major goal of cultural psychology is to have many and varied cultures contribute to basic psychological theories in order to correct these theories so that they become more relevant to the predictions and explanations of all human behaviors, not just Western ones; this goal is shared by many of the scholars. In an attempt to show the interrelated interests of cultural and indigenous psychology, cultural psychologist Pradeep Chakkarath emphasizes that international mainstream psychology, as it has been exported to most regions of the world by the so-called West, is only one among many indigenous psychologies and therefore may not have enough intercultural expertise to claim, as it does, that its theories have universal validity.
The acronym W. E. I. R. D. Describes populations that are Western, Industrialized and Democratic, thus far, W. E. I. R. D. Populations have been vastly overrepresented in psychological research. Findings from psychology research utilizing W. E. I. R. D. Populations are labeled as universal theories and are inaccurately applied to other cultures. Recent research is showing that cultures differ in many areas, such as logical reasoning and social values; the evidence that basic cognitive and motivational processes vary across populations has become difficult to ignore. For example, many studies have shown that Americans and western Europeans rely on analytical reasoning strategies, which separate objects from their contexts to explain and predict behavior. Social psychologists refer to the "fundamental attribution error" or the tendency to explain people's behavior in terms of internal, inherent personality traits rather than external, situational considerations. Outside W. E. I. R. D. Cultures, this phenomenon is less prominent, as many non-W.
E. I. R. D. Populations tend to pay more attention to the context. Asians tend to reason holistically, for example by considering people's behavior in terms of their situation, yet many long-standing theories of how humans think rely on the prominence of analytical thought. By studying only W. E. I. R. D. Populations, psychologists fail to account for a substantial amount of diversity of the global population. Applying the findings from W. E. I. R. D. Populations to other populations can lead to a miscalculation of psychological theories and may hinder psychologists' abilities to isolate fundamental cultural characteristics. Mutual constitution is the notion that the society and the individual have an influencing effect on one another; because a society is composed of individuals, the behavior and actions of the individuals directly impact the society. In the same manner, society directly impacts the individual living within it; the values and ways of life a society exemplifies will have an immediate impact on the way an individual is shaped as a person.
The atmosphere that a society provides for the individual is a determining factor for how an individual will develop. Furthermore, mutual constitution is a cyclical model in which the society and the individual both influence one another. While cultural psychology is reliant on this model, societies fail to recognize this. Despite the overwhelming acceptance that people affect culture and culture affects people, societal systems tend to minimize the effect that people form on their communities. For example, mission statements of businesses and foundations attempt make promises regarding the environment and values that their establishment holds. However, these promises cannot be made in accordance with the mutually consisting theory without being upheld by all participants; the mission statement for the employees of Southwest Airlines, for example, makes th
Behavioural genetics referred to as behaviour genetics, is a field of scientific research that uses genetic methods to investigate the nature and origins of individual differences in behaviour. While the name "behavioural genetics" connotes a focus on genetic influences, the field broadly investigates genetic and environmental influences, using research designs that allow removal of the confounding of genes and environment. Behavioural genetics was founded as a scientific discipline by Francis Galton in the late 19th century, only to be discredited through association with eugenics movements before and during World War II. In the latter half of the 20th century, the field saw renewed prominence with research on inheritance of behaviour and mental illness in humans, as well as research on genetically informative model organisms through selective breeding and crosses. In the late 20th and early 21st centuries, technological advances in molecular genetics made it possible to measure and modify the genome directly.
This led to major advances in model organism research and in human studies, leading to new scientific discoveries. Findings from behavioural genetic research have broadly impacted modern understanding of the role of genetic and environmental influences on behaviour; these include evidence that nearly all researched behaviors are under a significant degree of genetic influence, that influence tends to increase as individuals develop into adulthood. Further, most researched human behaviours are influenced by a large number of genes and the individual effects of these genes are small. Environmental influences play a strong role, but they tend to make family members more different from one another, not more similar. Selective breeding and the domestication of animals is the earliest evidence that humans considered the idea that individual differences in behaviour could be due to natural causes. Plato and Aristotle each speculated on the basis and mechanisms of inheritance of behavioural characteristics.
Plato, for example, argued in The Republic that selective breeding among the citizenry to encourage the development of some traits and discourage others, what today might be called eugenics, was to be encouraged in the pursuit of an ideal society. Behavioural genetic concepts existed during the English renaissance, where William Shakespeare first coined the terms "nature" versus "nurture" in The Tempest, where he wrote in Act IV, Scene I, that Caliban was "A devil, a born devil, on whose nature Nurture can never stick". Modern-day behavioural genetics began with Sir Francis Galton, a nineteenth-century intellectual and cousin of Charles Darwin. Galton was a polymath who studied many subjects, including the heritability of human abilities and mental characteristics. One of Galton's investigations involved a large pedigree study of social and intellectual achievement in the English upper class. In 1869, 10 years after Darwin's On the Origin of Species, Galton published his results in Hereditary Genius.
In this work, Galton found that the rate of "eminence" was highest among close relatives of eminent individuals, decreased as the degree of relationship to eminent individuals decreased. While Galton could not rule out the role of environmental influences on eminence, a fact which he acknowledged, the study served to initiate an important debate about the relative roles of genes and environment on behavioural characteristics. Through his work, Galton "introduced multivariate analysis and paved the way towards modern Bayesian statistics" that are used throughout the sciences—launching what has been dubbed the "Statistical Enlightenment"; the field of behavioural genetics, as founded by Galton, was undermined by another of Galton's intellectual contributions, the founding of the eugenics movement in 20th century society. The primary idea behind eugenics was to use selective breeding combined with knowledge about the inheritance of behaviour to improve the human species; the eugenics movement was subsequently discredited by scientific corruption and genocidal actions in Nazi Germany.
Behavioural genetics was thereby discredited through its association to eugenics. The field once again gained status as a distinct scientific discipline through the publication of early texts on behavioural genetics, such as Calvin S. Hall's 1951 book chapter on behavioural genetics, in which he introduced the term "psychogenetics", which enjoyed some limited popularity in the 1960s and 1970s. However, it disappeared from usage in favour of "behaviour genetics"; the start of behavior genetics as a well-identified field was marked by the publication in 1960 of the book Behavior Genetics by John L. Fuller and William Robert Thompson, it is accepted now that many if not most behaviours in animals and humans are under significant genetic influence, although the extent of genetic influence for any particular trait can differ widely. A decade in February 1970, the first issue of the journal Behavior Genetics was published and in 1972 the Behavior Genetics Association was formed with Theodosius Dobzhansky elected as the association's first president.
The field has since diversified, touching many scientific disciplines. The primary goal of behavioural genetics is to investigate the nature and origins of individual differences in behaviour. A wide variety of different methodological approaches are used in behavioral genetic research, only a few of which are outlined below. Animal behavior genetic studies are considered more reliable than are studies on humans, because animal experiments allow for more variables to be manipulated in the laboratory. In animal research selection experiments have been employed