Historical and conceptual issues in psychology, by Brysbaert, M and Rastle, K (second edition) - a summary
- 4318 keer gelezen
Foundation of psychology
Chapter 13
Psychology and society
Science overtakes religion in Western society
Initial strong links between psychological thinking and religion
Psychology as a separate branch of knowledge grew out of the rising role of scientific thinking in Western society.
Education for a long time was controlled by the churches, which did not look favourably upon those who tried to examine the soul.
Many early psychologists had strong connections with religion.
Alliance formation with the expanding sciences
Rapidly, the experimental psychologists distanced themselves from religion, because it jeopardies their scientific credentials.
They sought to align themselves with the rapidly growing natural sciences, by denouncing weaker fields that might contaminate them, such as religion, philosophy, and sociology.
Psychologists replace pastors
Fewer people felt comfortable discussing their mental health problems with religious authorities.
Whereas for a long time churches were the first port to call for mental health problems, growing secularisation increased the need for non-religious counselling.
At the same time, a growing number of clergy started to study psychology to improve the help they were able to provide.
Changes in society impinge on psychological practice
Impact on psychological research
The massive changes in the organisation of Western society in the nineteenth and twentieth century generated ideas and research opportunities for psychologists.
Six historical developments that affected psychological research
Societal influences were not limited to the science-oriented track of psychology, but also shaped thought in the hermeneutic part.
Impact on clinical practice
Changes in society influenced clinical practice.
Mental disorders show cultural variation.
This is not only true between cultures, but also across time within a culture.
Each culture has a symptom pool, a collective memory of how to behave when ill.
At each time period patients with psychological problems gravitate towards the symptoms that at the time are thought to be legitimate indications of disease, as no patients wants to select illegitimate symptoms.
Society as a metaphor provider
Metaphors: in science, stands for an analogy from another area that helps to map a new, complex problem by making reference to a better understood phenomenon.
The wider world has influenced psychology by the provision of metaphors.
Examples of metaphors in psychology
Psychologists have used four types of metaphors:
The power of metaphors
Metaphors in science are not just comparisons.
They allow researchers to formulate an test hypotheses on the basis of the analogy, which otherwise would have remained elusive.
Metaphors work because they transfer a complex knowledge system from a known theme to an unknown topic.
At the same time, they include a danger, because often the phenomenon to be understood does not completely fit into the metaphor.
The metaphor does not replace reality, it only allows the researchers to get a grasp of some aspects of the phenomenon.
Throughout history, scientific innovations have been a source of metaphors to understand the mechanisms of the mind.
By applying them, psychologists got a better grip on the phenomena they tried to understand.
At the same time, metaphors restrict understanding, because the phenomenon to be explained is rarely exactly the same as the analogy used
Socio-political biases in psychological theories
Scientific research does not happen in a void but is influenced by the culture in which the researchers live.
Even measurements and data are not safe in the light of strong socio-politico opinions. Gould vs. Morton
Gould
Showed how easy ‘objective’ findings can be distorted by the researchers’ expectations.
The observation that the same data set can lead to different conclusions is a useful reminder of the fact that data collection and measurement involve selection and interpretation, which make scientific conclusions open to socio-political influences.
Money and Ehrhardt (1972). The trainability of gender identity
Socio-political biases in scientific conclusions are not limited to the biological perspective.
An example of current social influences: hidden racism
Hidden racism: advancing one’s own race by non-conspicuous biases against other groups (usually by ignoring their contribution).
Socio-political influences on psychological practice
The socio-political contexts also influences the conditions under which psychologists work.
An increased interest in ethical issues
One of the developments of the last decades is an increased concern for ethical issues.
Two big social changes lie at the heart of this shift
Litigation and importance of documented evidence
The same biases apply to all kinds of knowledge and the non-scientific approaches have fewer defences against them.
Mechanisms that allow others to evaluate the claims researchers make and present counter-evidence
Because of these requirements, scientific knowledge is among the most trustworthy we have.
Psychologists as pawns in power games
Psychologists as a group are entangled in the struggle for power in various groups.
They try to improve their standing by manipulating other, but at the same time are constantly being used by other groups as part of their power struggle.
Foucault and the power of discipline
Michel Foucault (1926-1984)
Published a book in which he discussed how rules discipline their inferiors
Within Foucault’s world view, the primary role of psychologists is to help with the surveillance of mental health patients, students, employees and everyone else they are asked to assess and advise.
The main task of psychologists is not to help clients, but to keep them in line with the prevailing social organisation.
Foucault’s view on madness
Foucault described how societies need outcasts, because their exclusion makes everyone else feel better.
The misuse of psychological knowledge by pseudoscientists
Another way in which psychologists have been used by society is that their knowledge has been hijacked by groups who did not subscribe to the scientific ethos.
Psychological knowledge has been recycled by individuals who were not primarily interested in the truth of the findings, but in the extent in which they advanced their own case.
The essential element of pseudo-psychology is that evidence-based statements are freely combined with made-up statements, statements from dubious sources and statements that are known to be wrong.
In most countries the problem is not that existing psychologists are abusing their powers, but to protect clients from bogus therapists.
The misuse of psychological knowledge in times of war
Psychological knowledge may become misused against people by psychologists themselves.
Interim summary
The ways in which society has influenced psychology
The psychologisation of society
The impact psychology has on the way in which people interact is enormous.
Psychologisation: word used in two different meanings
Psychology has changed how people perceive each other
Labels introduced by psychology become real
Many of the concepts through which people differentiate themselves come from psychological writings.
Many psychological concepts became part of everyday life, once they had been coined.
Labels introduced by psychology change the subject of psychology
The introduction of new concepts by psychology not only changes the social reality for other people but also for psychologists.
New psychology students wrongly believe that the concepts currently used in psychology and the wider culture refer to ‘natural personal qualities’, which have always been there and not to qualities that, to some extent, are the result of prior developments in psychological research.
As a result of previous research the subject matter observed by psychologists today is different from the subject matter observed in the past.
Psychological labels are to some extent arbitrary
New psychological concepts not only make new realities, but also define them in arbitrary ways, because the concepts have been introduced without a good understanding of what was involved.
Society adapts to the label
Once a psychological label has become reality, society starts to adapt itself to the new measure, thereby further increasing the reality of the concept.
Psychologists make friends
Educational psychology
The first group that welcomed input from psychology was the educationalists.
Psychologists swiftly became involved in educational matters.
Psychologists and teachers agreed that psychology was a core component of a teacher’s qualification.
In addition, psychology started to introduce intelligence tests in schools and began to lobby for school counsellors.
Advising parents
From its stronghold in schools, it was a small step to also raid the fledgling literature of parenting.
Psychologists create needs
Institutions for monopolies by creating needs
Once a new section of society is established, they try to increase their slice of the economy by creating new needs.
Illich’s account of medicine
Illich argues that the medical and pharmaceutical worlds enormously overstate their significance for the health of people.
The extension to psychology
According to sociologists, psychologists are not in the first place interested in helping people, but in creating needs so that they can expand their industry.
Psychologists promote values
Psychologists spread Western views of wellness and healing around the world
Psychologists, together with medical practitioners, contribute to spreading the therapeutic ethos across the world.
Psychologists are not politically neutral
Psychologists within the Western world are not politically neural.
Although psychologist celebrate diversity, recognize the value and legitimacy of diverse beliefs and by their own admission strive to be inclusive, conservatives are a vastly under-represented and marginalised minority in psychology.
As a consequence of their bias, psychology departments are a force in the promotion of left and liberal values in the society.
Redding (2001)
The liberal bias of psychologists has consequences for psychology’s standing in society
Psychology increases the weight of science in the competition with the humanities
Psychology as a discipline has largely promoted the virtues of the scientific approach and downplayed the contribution of the humanities.
Many psychology researchers in their communication with the general public stress the superiority of their findings relative to common knowledge, because their findings are based on scientific evidence.
Psychologists are not neutral to religion
Psychologists tend to have rather sceptical views about religion.
Few psychologists are able to see religion as a source giving meaning to life and adversity.
Even if psychologists do not talk openly about their religious views, in subtle ways their attitudes impose values on people they work with
Interim summary
Critical views about the ways in which psychology has influenced society
Interim summary
To what extent is the psychologisation of society steered by psychologists?
JoHo can really use your help! Check out the various student jobs here that match your studies, improve your competencies, strengthen your CV and contribute to a more tolerant world
Foundation of Psychology
Chapter 1
The wider picture, where did it all start?
Introduction
This book describes the growth of psychology as an independent branch of learning and tries to comprehend the essence of the discipline.
The introduction of written records represents one of the most important moments in the development of science.
The preliterate culture
Preliterate civilisation: civilisation before writing was invented.
Though these civilisations have not left us with written testimonies, it is possible to discern several important features of them by studying existing cultures that do not use writing.
This research revealed three important characteristics of knowledge in these kinds of cultures:
The first writing systems
Written language appeard separately in at least four cultures:
These four written languages were preceded by protowriting, the use of symbols to represent entities without linguistic information lining to them.
Characteristics of writing systems
From an early stage, writing systems were a combination of pictograms and phonograms.
Pictogram: an information-conveying sign that consists of a picture resembling the person, animal or object it represents.
Phonogram: a sign that represents a sound or a syllable of spoken language.
Phonograms were gradually replaced by simpler signs symbolizing meaningful sounds in language, (phonemes or syllables).
The use of phonograms to represent phonemes led to the alphabetic writing systems.
Logograph: a sign representing a spoken word, which no longer has a
.....read moreFoundation of Psychology
Chapter 2
The scientific revolution of the seventeenth century and its aftermath
Introduction
The word psychology did not appear in literature before 1500.
Scientific revolution: name given to a series of discoveries in the seventeenth century, involving Galilei, Descartes and Newton, that enhanced the status of science in society.
The geocentric model of the universe in the sixteenth century
The earth as the centre of the universe
The model that of the universe used in the sixteenth century was the model described by Aristotle who built on others) and elaborated by Ptolemy.
Aristotle’s universe was a limited universe with the Earth in the middle
Geocentric model: model of the universe in which the Earth is at the centre; was dominant until the seventeenth century.
The addition of epicycles
A key problem within the Aristotelian universe was the movements of some of the wandering stars.
To explain strange movements, Ptolemy used the notion of ‘epicycles’.
Epicycles: small cycles made by the wandering stars in addition to their main orbit around the earth.
Copernicus’s alternative heliocentric model
The sun at the centre of the universe
Aristotle’s model was not the only one that had been proposed in ancient cultures.
Heliocentric model: model of the universe in which the sun is at the centre.
Copernicus saw the heliocentric model as a valid alternative for the geocentric model.
Why Copernicus waited to publish his model
Only shortly before his death, Copernicus was persuaded to get his book printed.
Possible reasons
Galilei uses a telescope
Because of the many problems with Copernicus’s model, it failed to have much impact.
Galilei’s observations
Galilei built a telescope and found out that:
Foundation of Psychology
Chapter 3
Eighteenth- and nineteenth- century precursors to a scientific psychology
A characteristic of current Western society is that people derive their self-image and self-esteem from their own qualities and accomplishments rather than from the position of their family in society.
Individualisation: trend in a society towards looser social relations and a greater focus by individuals on themselves than on the groups they belong to.
Historians believe that this process of individualisation started sometime around the end of the Middle Ages and is still growing.
Following factors are contributions:
Interim summary
Since the end of the middle ages there has been increasing individualisation in society. Factors hypothesised to play a role include:
Descartes was the first Western philosopher after the Ancient Greeks to value new and independent thinking.
Epistemology: branch of philosophy concerned with the nature of knowledge.
Empiricism instead of rationalism
The traditional rationalist
.....read moreFoundation of psychology
Chapter 4
Establishing psychology as an independent academic discipline
By 1850 there was a thriving literature of psychological subjects in Germany.
The universities reform in Germany
Universities in the German states for a long time were dominated by the humanities and religion.
This was a feature proponents of the Enlightenment fought against.
The Enlightenment ideas mainly came from a group of academics who had been expelled from the University of Leipzig, because of their critical attitude and modern ways of thinking.
A reform took place after the defeat of the Holy Roman Empire in 1805-1806.
The defeat by the French particularly upset the Prussians, who decided it was high time to modernise their country.
The school system was reorganised and a new university model was installed.
The emphasis on scientific research and the freedom given to the professors made the German universities dynamic and open to new areas for scientific investigation.
Wundt and the first laboratory of experimental psychology
Wundt’s career
After this Phd in medicine, he obtained an assistantship with Hermann von Helmholtz where Wundt began to identify himself as a scientific psychologist.
In 1862 he gave his first course in ‘Psychology as a natural science’ and in 1874 he published a book on physiological psychology.
In the book, psychology was defined as the study of the way in which persons look upon themselves, on the basis of internal physiological changes that inform them about the phenomena perceived by the external senses.
Wundt called his psychology physiological because:
Foundations of psychology
Chapter 5
Strengthening the scientific standing of psychology
The USA began to rule psychology in the twentieth century.
The expansion of psychology around the start of the twentieth century
As well as laboratories, in 1892 the American Psychological Association (APA) was founded, giving psychology researchers a forum to meet and discuss their findings.
Two journals were established that would dominate the field and that still exists today.
The first American psychology: functionalism
As psychology in the USA expanded, it got moulded by the expectations and preoccupations of American society.
There was a mistrust of intellectualism, knowledge for the sake of knowledge.
America was a nation of common-sense businessmen, not interested in abstract science, but in practical accomplishments that at the same time made money, revealed God’s glory, and advanced the American dream.
If psychology were to prosper, it had to subscribe to American values, which it readily did.
Part of the attraction to the functionalist approach to the Americans was that Wundt’s experimental research programme ran into problems in 1880s.
Psychology and its position within universities
Most psychology laboratories were set up within philosophical and theological institutes.
Staff members were not always happy with this.
On other occasions experimental psychologists were told not to stay too far from good old psychology as developed in philosophical writings.
Trying to win over the public
Phrenology
Phrenology: view that mental functions are localised in the
.....read moreFoundations of psychology
Chapter 6
The input from brain research
Beliefs of the ancient Egyptians
The Edwin Smith papyrus
In 1862 an American collector, Edwin Smith, bought a papyrus scroll in the Egyptian city of Luxor.
In the text, written around 1700 BCE, but probably a copy of an older papyrus from 3000 BCE, a series of 48 cases were described dealing with the consequences of head and neck injuries.
Each case included a title, details of the examination, a diagnosis and an indication of the treatment.
The diagnosis consisted of one of three conclusions
The Edwin Smith papyrus: papyrus from Ancient Egypt that contains short descriptions of the symptoms and treatment of different forms of brain injury; named after the person who bought the papyrus in Egypt and had it analysed.
They illustrate how physicians treating wounded soldiers quite early became convinced of the importance of the head (brain) in controlling behaviour.
Beliefs in the wider society
The existence of the Edwin Smith papyrus did not imply that the knowledge contained in it was widespread.
In Ancient Egypt most scholars were convinced that the heart was the seat of the soul.
The roles of the heart and brain in Ancient Greece
The discussion over whether the soul was in the heart or in the brain continued in Ancient Greece.
Plato
Plato and Hippocrates placed the soul in the brain.
Plat also saw a function for the heart.
According to Plato, the soul was divided into three parts
Aristotle
Aristotle was convinced that the heart was the seat of the soul.
The function of the brain was to counterbalance the
Foundations of psychology
Chapter 7
The mind-brain problem, free will and consciousness
Throughout history, humans have been impressed by their ability to reflect about themselves and the world around them.
Self: the feeling of being an individual with private experiences, feelings and beliefs, who interacts in a coherent and purposeful way with the environment.
Mind-brain problem: issue of how the mind is related to the brain.
Three main views
Mind: aggregate of faculties humans (and animals) have to perceive, feel, think, remember and want.
Dualism: view of the mind-body relation according to which the mind is immaterial and completely independent of the body; central within religions and also in Descartes’ philosophy.
Dualism in religion and traditional philosophy
Religion
Dualism is central to religions.
They are grounded in the belief that people possess a divine soul created by God, which temporarily lives in the body, and which leaves the corpse upon its death.
The soul is what gives people their purpose and values in life.
It usually aims for the good, but can be tempted and seduced by evil forces.
This gave rise to the demonologist view of psychopathology.
Demonologists view: the conviction that mental disorders are due to possession by bad spirits.
Plato and Descartes
Dualism was central in the philosophies of Plato and Descartes.
Cartesian dualism: theories in which the mind is seen as radically different
.....read moreFoundation of psychology
Chapter 8
How did psychology affect everyday life?
Introduction
Over the course of the twentieth century, the discipline of psychology grew from a marginal academic field to a discipline that has done more than any other to transform the routines and experiences of everyday life.
Applied psychology: the application of psychological knowledge and research methods to solve practical problems.
Evolutions before World War II
Mental health problems must be treated by partitioners with a medical degree
Psychologists were not allowed to provide unsupervised therapies in official settings and their private practices were not covered by health insurance.
The first clinical psychology centres
Treatment centres run by psychologists started in the USA and were university-related.
Lightner Witmer
Opened the faculty that was the first psychology health centre in 1896.
Aimed at helping behavioural and learning problems in school children.
The founding of clinical psychology centres was impeded by the lack of support from academic psychologists.
In the meantime mental health problems and psychoanalysis became popular courses in psychology.
Clinical psychology: branch of psychology applying psychological knowledge to the assessment and treatment of mental disorders.
The first clinical psychology centre in the UK was set up in 1920 in a private house in London.
The impact of World War II
An urgent need for psychological advice and treatment
Shell-shock: anxiety response of battlefield that prevents soldiers from functioning properly; was one of the first topics addressed by applied psychology.
The finding of shell-shock in World War I gave rise tow two developments
When the USA decided to join World War II they also decided to properly staff the military psychiatric service.
A crash course in the treatment of mental disorders was offered to all medical officers, and clinical psychologists were taken on broad, both for testing and treatment.
The beginning of client-centred therapy
The rising demand for psychological help provided a rich environment for new developments in therapy.
Foundation of psychology
Chapter 9
What is science?
Science’s claim of superiority was based on four principles
Thoughts before the scientific revolution
Plato, Aristotle and the sceptics
Plato
A strong rationalist view of knowledge acquisition.
Human perception was fallible and the observable world was only a shadow of the Real world.
The human soul had innate knowledge of the universe, which could be harnessed
Aristotle
More scope for observation and made a distinction between deductive reasoning and inductive reasoning.
True, theoretical knowledge started from axioms, form which new knowledge was deduced via so-called demonstrations.
Perception was the source of information but not knowledge itself.
Correspondence theory of truth: a statement is true when it corresponds with reality. Assumes that there is a physical reality which has priority and which the human mind tries to understand it. First formulated by Aristotle.
Pyrrho of Ellis
Scepticism: philosophical view that does not deny the existence of a physical reality, but denies that humans can have reliable knowledge of it; first formulated by Pyrrho of Ellis.
Humans must suspend judgment on all matters of reality.
Augustine
Augustine (354-430CE)
True knowledge was knowledge based on God’s revelations.
This view became dominant until well into the seventeenth century.
Interaction between theory and experiment: the scientific revolution
Galilei’s thought experiments
Galilei is usually credited as the person who convinced the world of the importance of observation and experimentation for the acquisition of knowledge.
But Galilei might in reality be a transition figure steeped in the Aristotelian tradition.
Foundation of psychology
Chapter 10
Is psychology a science?
The foundation of psychology as an academic discipline was legitimised on two pillars
Psychology has a long, respectful past and uses the scientific method
Steven Ward
Makes the case that a new branch of knowledge can establish itself and survive only if it succeeds in convincing the ruling powers of the need for such knowledge as well as reassuring them that it is no threat to their prosperity.
The founders of psychology promoted it as a new academic discipline by stressing two messages
Consequences for the psychology curriculum
Because psychology was promoted on the basis of its long past and its sound method, both ‘history of psychology’ and ‘research methods’ were major components of the curriculum.
These books on history were self-legitimisation as much as essential stepping stones for a good psychology education.
Science is defined by its method rather than by its subject matter
Every topic studied within the scientific method is a science
To be accepted as a science, psychologists had to make the case that what differentiated sciences from non-sciences was the way in which problems were investigated, and not the type of problems addressed.
Although few people spontaneously associated the study of mental life with scientific research, the first academic psychologists maintained that there was nothing inherent in the subject matter that prevented it from being studied using the scientific method.
Methodolatry
Because of its emphasis on method in the definition of science, academic psychology invested heavily in developing appropriate research designs and analysis techniques.
It has been argued that psychology throughout its existence has overplayed the role of research methods at the expense of theory building.
Methodolarty or methodologism: tendency to see methodological rigour as the only requirement for scientific research, at the expense of theory formation.
The shadow of positivism
One reason why psychologists tended to stress valid testing rather than theory formation was that they tried too hard to be good scientists.
Foundation of psychology
Chapter 11
The contribution of quantitative and qualitative research methods
Quantitative research methods: research methods based on quantifiable data; are associated with the natural-science approach based on the hypothetico-deductive method.
Assumptions underlying quantitative research methods
There is an outside reality that can be discovered
Quantitative psychologists start from the assumption that phenomena in the world have an existence outside people’s minds.
They defend the idea that humans can discover reality by using the scientific method.
They are well aware of the fact that science is not a linear accumulation of facts but proceeds through trial and error. But are convinced that in the long term the scientific method based on the hypothetico-deductive model leads to an understanding of reality → scientific knowledge is cumulative
The main aim of scientific research is to find universal causal relationships
Researchers are primarily interested in discovering relationships between causes and effects.
How general are principles? And how do humans function?
Ideally they hope the mechanisms they discover will apply to all humans.
Trying to avoid confounds and sources of noise
Users of quantitative research methods are extremely vigilant about the possible intrusion of undesired factors into their designs.
They try to maximally control the circumstances under which they run their studies
They also try to eliminate the impact of random variables called noise.
Suspicion about the researcher’s input
A source of confounding and noise that is of particular interest to quantitative psychology researchers is the researcher him- or herself.
To protect themselves against biases and noise, quantitative researchers make use of standardised measurements and instruments.
Progress through falsification
Researchers constantly try to prove each other wrong.
Research methods are divided into three broad orientations
Descriptive research
Observation of numerical data
Detailed observation is the start of scientific research.
Typical for quantitative research is that the data are gathered in a numerical form, either by collecting measurements or by counting frequencies of occurrence.
Before researchers collect data, they have a good idea of how they will analyse them; what types of measurements they will obtain and what types of statistics they can apply to summarise and evaluate the data.
Large samples and a few data points per participant
The vast majority of descriptive quantitative studies involve the collection of a limited amount of data from a
.....read moreFoundation of psychology
Chapter 13
Psychology and society
Science overtakes religion in Western society
Initial strong links between psychological thinking and religion
Psychology as a separate branch of knowledge grew out of the rising role of scientific thinking in Western society.
Education for a long time was controlled by the churches, which did not look favourably upon those who tried to examine the soul.
Many early psychologists had strong connections with religion.
Alliance formation with the expanding sciences
Rapidly, the experimental psychologists distanced themselves from religion, because it jeopardies their scientific credentials.
They sought to align themselves with the rapidly growing natural sciences, by denouncing weaker fields that might contaminate them, such as religion, philosophy, and sociology.
Psychologists replace pastors
Fewer people felt comfortable discussing their mental health problems with religious authorities.
Whereas for a long time churches were the first port to call for mental health problems, growing secularisation increased the need for non-religious counselling.
At the same time, a growing number of clergy started to study psychology to improve the help they were able to provide.
Changes in society impinge on psychological practice
Impact on psychological research
The massive changes in the organisation of Western society in the nineteenth and twentieth century generated ideas and research opportunities for psychologists.
Six historical developments that affected psychological research
Societal influences were not limited to the science-oriented track of psychology, but also shaped thought in the hermeneutic part.
Impact on clinical practice
Changes in society influenced clinical practice.
Mental disorders show cultural variation.
This is not only true between cultures, but also across time within a culture.
Each culture has a symptom pool, a collective memory of how to behave when ill.
At each time period patients with psychological problems gravitate towards the symptoms that at the time are thought to be legitimate indications of disease, as no patients wants to select illegitimate symptoms.
Society as a metaphor provider
Metaphors: in science, stands for an analogy from another area that helps to
.....read moreThis is my personal collection of content about the history of psychology
The invention of writing
The discovery of numbers
The Fertile Crescent
Civilisations in the Fertile crescent:
The Greeks
Developments from the Roman Empire to the end of the Middle Ages
Ancient Romans:
Byzantine empire
Arab empire:
Western Roman empire:
Introduction
Mind-brain problem: issue of how the mind is related to the brain.
Three main views
Dualism
Materialism
Functionalism
In this magazine, you can find the summaries you need to finish the course foundations of psychology in the second year of the study psychology at the uva.
There are several ways to navigate the large amount of summaries, study notes en practice exams on JoHo WorldSupporter.
Do you want to share your summaries with JoHo WorldSupporter and its visitors?
Field of study
Add new contribution