Is Psychology a science and should it be?
Psychology is the study of human and animal behaviour, experience and the mind, which aims to give society an understanding of human nature and subsequently help to improve it. Psychology, as a discipline, has been dotted with different approaches and theories, as demonstrated by the early experiments of Wilhelm Wundt (1850’s), to the conditioning programmes of Pavlov (1920’s) to contemporary discourse analysis of the social constructionist. Psychology has been continuing through the years, changing its tact due to new discoveries and the development of improved technologies or ways of thinking (Richards, 1996). Psychology can thus be seen as a new discipline attempting to find itself and ground itself within scientific knowledge in order to gain credibility when perhaps this should not be the case. Although psychology may use scientific methods this paper will highlight the fact that psychology is not a science and should not be or become a science.
A science is defined by Popper (1972, 1959) as being a discipline, in which rigorous scientific testing, namely experimentation, proceeds to falsify theories and hypotheses. Theories and hypotheses that cannot be falsified therefore can be held to be true but must continuously be reassessed through falsification. Falsification is viewed by Popper as more important than that of verification due to the fact that any theory can be supported through evidence, whether this is weak or strong, however evidence can be wrong. By attempting to falsify theories, scientists can be viewed as objective. According to such philosophical views of science a theory, hypothesis or perspective that does not open itself to falsification is not scientific nor a science. For example, Popper (1972, 1959) argued against psychoanalysis due to this very fact. Proponents of psychoanalysis did not allow for falsification in that all theories and hypotheses became completely cyclical thus such theories could not be falsified hence Popper refuted psychoanalysis’ claim to science (Elliot, 1999, 1994; Frosh, 1999, 1997; Popper, 1972, 1959). Furthermore, Kuhn (1962) argues that there is little evidence that scientists and psychologists rarely follow the falsification methodology. Hence, according to this, psychology is not a science as according to Popper as researchers do not attempt to falsify their hypotheses.
A key assumption of a science is that of operationalism. In other words, science attempts to take objective and accurate measurements of the variables. Behaviourism was psychology’s attempt of being purely objective and thus more scientific. However, to its disadvantage, behaviourism removed the core constructs underpinning psychology, that of mental states, in its attempt to be more objective. Thoughts and feelings cannot be objectively or directly observed, which challenges the concept of operationalism (Hirschorn, 1979, as cited by Medcof & Roth, 1979; McLeish, 1963; Popper, 1959).
It is the case that in modern society particularly that of Western societies, emphasis is placed upon science as trustworthy and credible (Bem & Huib, 1997). Throughout the history of psychology, psychologists have attempted to distinguish psychology as a science and consequently psychology is viewed incorrectly by the population as a science. Hence, mainstream psychology is characterised by a “fetish for quantification” (Parker, 1994, p 4) used in order to gain acceptance from society as a full science and gain the credibility that a science can bring (Bem & Huib, 1997). Thus, it can be said that proponents of the scientific paradigm are attempting to make this paradigm a driving force for psychology in order to give psychology more credibility. This does not make psychology a science; it does however exemplify the fact that psychology takes advantage of both scientific and non-scientific methods in the pursuit of the truth. However, Parker (1994) believes that there is a considerable difference between the ideal of science that some psychologists, mainly quantitative researchers, hold and the true nature of science.
Freud (1933, p. 198) stated that “Philosophy is not opposed to science, it behaves itself as if it were a science, and to a certain extent it makes use of the same methods”. Although this statement was intended to support the use of the scientific approach within psychology, it supports the argument that psychology is not science and more similar to philosophy. In other words, psychology can be seen as not opposite to science but behaves in a scientific manner, using similar methods to the natural sciences however; psychology is not a science as it uses qualitative methods, which are not scientific. This is not to say that psychology is a philosophy, it is the study of human behaviour and experience but the statement implies that psychology is similar to science but it is not a science.
On a similar note, McGhee (2001) argues that psychology is partly scientific however it is not wholly scientific, in the sense that certain approaches use scientific methods to investigate behaviour whereas others do not. For example, social constructionism uses qualitative methods, such as discourse analysis, which are seen to be unscientific.
Quantitative researchers wish to study and measure behaviour, and to some extent, cognitions objectively, in order to predict behaviour (Parker, 1994). To some extent behaviour can be said to be predictable, for example, the time an individual wakes up or the score an individual will receive upon a second administration of the same intelligence test, however, it is clear that behaviour is not always predictable on the grounds of observable, physical factors. Valentine (1982) argues that behaviour is only predictable when it is understood with regards to the meaning that the individual attributes to such factors. This is again contrary to the constructs of scientific research, as meaning can be seen as a subjective experience, which cannot truly be quantified (Silverman, 1993).
Consciousness, as part of the subject matter of psychology, is seen as being unpredictable, or at least, to some extent, it cannot be observed in a way that would lead to predictions being made. Furthermore, consciousness is unsuitable for scientific study due to the fact that it is a metaphysical entity and thus, so far within psychology, the consciousness has been inferred improperly, possibly incorrectly by observations of behaviour and physiology with disregard for the complexities of consciousness (Valentine, 1982). Scientific/quantitative research into such phenomena can allow for only limited responses if it is to satisfy the systematic and rigorous constructs of the scientific ideal/paradigm (Silverman, 1993). Thus, such methods limit expression of perception and thus reduce the validity of such findings. It can be said with some certainty that methods that cannot deliver valid interpretations of human consciousness and the mind cannot be deemed worthy in its use. Hence, the compulsion of some researchers to use quantitative methods may be misguided, as psychology cannot be a science due to the nature of its subject matter.
Medcof (1979, as cited by Medcof & Roth, 1979) states that technology within psychology is not sophisticated enough to deal with subjective experience. Hence, Medcof claims that technology needs to advance to a state whereby such study can take place in order for psychology to become a true science. However, though quite dated as this statement is, it still stands as a valid statement and thus, if subjective experience cannot be measured scientifically then psychology should not attempt to do so. Thus, psychology should not be nor become a science for this fact.
Qualitative methods used prior to and then in conjunction with quantitative methods may be seen as scientific or at least more valid, however, this is hardly a premise to claim that psychology as a discipline is a science. Psychology is the study of human behaviour and experience: both scientifically and non-scientifically (Gough & McFadden, 2001; Hepburn, 2003; McLeish, 1963).
Within the history of psychology, qualitative research has been used as a preliminary source of information and has been viewed with distain as an unscientific method. However, qualitative research is attempting to establish itself as a legitimate and valid form of study. Recently qualitative researchers have become increasingly unsatisfied with the discourses of negativity imposed upon their form of enquiry by quantitative researchers (McGhee, 2001; Silverman, 1993; Sternberg, 2005). This is demonstrated in discourse analysis, as this form of enquiry is becoming ever-increasingly popular with qualitative researchers. Furthermore, the use of such methods as triangulation and reflexivity add context and validity to such research, which is increasing acceptance of qualitative research as appropriate research (Hepburn, 2003; Gough & McFadden, 2001).
An issue that must be addressed is the question of explaining “difficult” issues within psychology, such as individual perceptions of emotional states? As the scientific paradigm cannot objectively measure such issues, are non-testable elements to be treated as non-existent and thus denying the truth? It is the case that quantitative methods cannot explain or measure the entirety of human behaviour or the mind , such demonstrated with my above reference to consciousness (McGhee, 2001; Parker, 1994; Silverman, 1993).
There is no denying the fact that qualitative research is inadequate with regards to systematic, rigorous testing of human behaviour and cognition as seen in quantitative research. However, I think the main point to highlight at this place within this answer is that undeniably the use of qualitative methods is the only adequate way of truly understanding the mind (McGhee, 2001; Silverman, 1993). Wetherell (1996) states that controlled experimentation is inadequate for the study of human behaviour, which is too complex for the linear laws and constructs of the experimental paradigm.
Psychology can be seen as needing both types of method if it is to truly understand its subject matter. It is the case that psychology is not a science due to the fact that unsystematic, unscientific methods are used and can be seen as useful. In addition, psychology should not be or become a science because of this need to use qualitative research to understand the mind. I think it is safe to say that without qualitative research, psychology would be reduced to a science of behaviour, rather than the study of behaviour, experience and mind, which would be a travesty: a failure to humanity.
According to McLeish (1963), psychology is a science of behaviour and so should not be open to bias of subjectivity however, such branches of psychology, such as social constructionism, advocate qualitative methods which rest upon researchers experience and opinion (Burr, 1995; McGhee, 2001; Willig, 2001). It is in this sense that I also argue that psychology is not a science in the same respect as the natural sciences, even a science at all, due to the nature of human psychology. Furthermore, it is due to this fact that psychology should not be a science and can never become a science similar to that of chemistry, biology and physics.
Opponents of the behaviourist approach criticised it for being overly mechanistic, viewing individuals almost as robots, operating in a purely stimulus-response manner. Thus, behaviourism ignored internal processes and mental states, such as consciousness and emotions, in order to study human behaviour scientifically. In other words, behaviourism ignored subjective experience, which cannot be denied as being one of the main constructs of human psychology. However, the behaviourist approach can be seen as allowing human and animal behaviour to be measured by means of experimental science, continuing the same rigorous, systematic work of William Wundt. Therefore, behaviourism attempted to be scientific in its approach to the study of behaviour and in this sense it can be claimed that psychology was attempting to move into the realms of science (Hirschorn, 1979, as cited by Medcof & Roth, 1979).
The problem that confronted behaviourism was that it could not contend with complex behaviour and how it was organised (Richards, 1996). The failure of behaviourism is an example of psychology’s attempt of being scientific as being unsuccessful. If a branch of psychology that attempts to be scientific, advocating an extreme reductionist position, does not last then surely this is an example that psychology is not and should not be a science (Hirschorn, 1979, as cited by Medcof & Roth, 1979). It is therefore obvious that the subject matter of psychology cannot be studied in a completely scientific and objective manner though the scientific method can aid us in the prediction and, to some extent, the explanation of human behaviour. Psychology cannot deny the existence of subjective experience, as behaviourism did, as subjective experience is part of our existence, and so psychology cannot become a science unless new technologies are created to objectively measure the full extent of subjective experience, however, there is little doubt in my mind that such technology would never encompass the entire extent of cognition or our perceptions of it.
Freud’s work could be construed as dated as it was written at a particular time and place but this merely demonstrates that psychological research is influenced by society and context, in Freud’s case this was a repressive society during contemporary anti-Semitism (Elliot, 1999, 1994; Frosh, 1999, 1997). Thus, psychology can be seen as changing with society and politics, which is seen with the natural sciences.
Freud’s work introduced ideas regarding individuals as irrational and subject unconscious desires and drives (Elliot, 1999). This is counter to later, now traditional psychological constructs of human behaviour as measurable and objective, hence the constructs of psychoanalysis advocates that psychology should not be a science, as unconscious desires cannot be measured scientifically.
From this psychology can be said to be not merely driven by science or even heading in a scientific direction, as seen in the application of psychoanalysis in modern society. For example, Horrocks’ (1995) psychoanalytic analysis of cinematic and written media regarding unconscious identification with characters within medium, demonstrates that psychological analysis is not always systematic or objective, as such analysis is based purely on researcher interpretation and so consequently this is a demonstration that certain aspects of the subject matter within the realms of psychology may be unsuitable for scientific study.
Friedenberg & Silverman (2006) state that cognitive psychology is interdisciplinary, incorporating multiple disciplines, including neuroscience, into this approach, using the methodologies of such disciplines. The authors claim that these methods could be deemed as characteristic of the ideology of science. However, the question I must ask is can such techniques and disciplines truly study the subjective experience of emotions?
In a similar sense, the problem with the cognitive approach is that there are many theories within this approach whilst no single theory can link the differing areas into a single coherent understanding/theory of cognition and human behaviour (Glassman, 1979, as cited by Medcof & Roth, 1979). Thus, as highlighted by Glassman (1979, as cited by Medcof & Roth, 1979) the cognitive approach demonstrates that isolated approaches alone cannot explain the vast expanse of human behaviour and experience.
Humanistic psychology claims that subjective experience is an important part of human behaviour and existence (Medcof, 1979, as cited by Medcof & Roth, 1979). Thus, the claim that psychology is a science can be said to be invalid as subjective experience cannot be quantified in any meaningful way, which could incorporate the whole arena of individual subjective experience.
In addition, the humanist approach measures human experience through data gathered from people’s perceptions of their self, which has been criticised for not fitting with empirical/scientific criteria, which is deemed as being non-scientific and thus not credible, as self-perception is not easily observable by others (Roth, as cited by Medcof & Roth, 1979).
The Humanistic perspective has had a certain degree of success within psychology, such as Maslow’s self-actualisation model, for example, but it only demonstrates that the study of human behaviour and experience may be unsuited to scientific study as humanistic study focuses solely on the individual, seeing each individual as different. Thus, how can such constructs cluster together to predict behaviour?
Contemporary/traditionalist social psychology has been criticised as being dominated and driven by the scientific paradigm (Gough & McFadden, 2001), which has led to the formation of social constructionism which has questioned the idea of objective fact and characterized psychology as value-laden and driven by vested interests (Willig, 2001; Burr, 1998).
Burr (1995) states that traditional psychology fails to take into account the personal dimension of identity. In other words, certain perspectives within traditional psychology ignore or suppress ideas of subjective experience in favour of the understanding generic, predictable human behaviour. For example, a neurological psychologist is more interested in the mechanisms and functioning of neural systems rather than how emotions can affect behaviour though it cannot be denied that they do not touch upon this.
Asch’s (1952, as cited by Gough & McFadden, 2001) classic experimental study of conformity can be used here as an argument against the use of scientific/experimental methods in psychology. Using objective stimuli that of differing line lengths, Asch attempted to assess whether individuals responded in a manner that was counter to their own perceptions in favour for the belief of the group. Asch’s study used scientific measures, such as observations of behaviour, as seen in the distress of the participant when responding in a manner that is incorrect. If the subject matter of psychology was wholly quantifiable then behaviour of ‘naïve’ participants would be predictable in that all participants would respond in keeping with the group. The results of Asch’s study suggest otherwise: on the one hand, thirty-three percent of participants conformed on half or more of the experimental trials whereas twenty-five percent of the sample did not conform on any of the trials. The conclusion drawn by Asch was that merely the presence of a group can make individuals conform, even when such behaviour is against their beliefs.
As Gough & McFadden (2001) point out, the study by Asch fails to take into account other influencing factors, such as identity, culture and historical practices, for example, as it focuses solely on the impact of a group upon the responses of an individual. Harre (1989) highlights the fact that ignoring the wider, more complex factors of human social life in experiments is a mistake to make with regards to understanding human social activity. Harre further states that such omissions are fundamental flaws of the experimental paradigm and thus ignores that which is essential to understanding human behaviour, such as personal identity, culture and historical practices (1952, as cited by Gough & McFadden, 2001). Thus, psychology can be seen as attempting to behave like a science, as mentioned with regards to Freud (1933), using similar methods however, when broken down, the methods employed to study psychology are not suited to subject matter and thus cannot, in my mind, be considered a science.
Reductionism refers to the scientific method of reducing the subject matter under investigation down to one single causal explanation. The use of reductionism is seen as a feature of scientific research and thus such research is held in high esteem for its ability to predict behaviour and explain it in a simple manner, however, due to the fact that such techniques ignore other influencing factors this reduces the validity of explanations (Friedenberg & Silverman, 2006; Bem & Huib, 1997).
In classic/traditional social psychology where the use of reductionism in the past enabled theories of crowd behaviour, for instance, to be formulated and tested, such as those of Le Bon’s (1895) theory and Zimbardo’s (1969) deindividuation model. However, such theories ignore the whole picture, decontextualizing the crowd and thus removing meaning from the situation (Reicher, 1996). Such techniques can be seen as removing truth/validity from the research. It can therefore be claimed that the use of reductionism leads to a failure to represent a full, truthful picture of human life. In light of this, should we cast aside ideals of truth in favour for the scientific ideal? The goal of science is the search for truth. However, the use of reductionism, especially in a discipline investigating the complex system of human life, reduces the validity of findings and so reduces the validity of any claims that psychology is a science, as the truth is not fully represented. Thus, this is a strong argument for the idea that psychology should not be or become a science due to the fact that the reductionist, scientific ideal could remove all truth from research and reduce psychology down to the neurochemical changes of the brain as the fundamental explanation of behaviour and experience, which naturally could not explain every aspect of human behaviour. Therefore, if the scientific ideal was taken up by all researchers, in the future psychology could be reduced to a brain science. However, alarming as it is the fact that human behaviour and experience is so complex that it cannot be reduced down to brain function alone, but seen as an interaction of many influencing factors.
The free-will/determinism debate relates to the argument that centres round whether the actions of individuals are determined by outside forces and/or prior events or whether the individual has a choice or act of will as to how to behave. The reason it applies to the present question is that a deterministic perspective is viewed as a scientific one in that it assumes that there is a physical cause of behaviour whereas the argument of free-will violates scientific assumptions of causation and thus as choice cannot be continuously predicted it cannot be accounted for in a scientific manner. Much of psychology takes on a deterministic outlook upon behaviour, such as developmental psychologists, who look upon behaviour as stemming from early experiences in childhood. Such a perspective is used in an attempt to explain behaviour through causal factors and is consequently seen as scientific because such perspectives can produce predictions of behaviour, however, it is my believe that determinism has detrimental effect upon truth, as a deterministic perspective ignores other influencing factors that may also have validity when explaining behaviour (Friedenberg & Silverman, 2006; Bem & Huib, 1997).
An argument against determinism is brought up within the realms of clinical psychology with regards to the causal factors and treatment of eating disorders, which can be seen as involving a wide array of factors, such as family, social factors and cognition and media influence, for example (Emmett & Rabinor, 2007; Little & Hoskins, 2004). Thus, an explanation and consequently treatment cannot be viewed in a deterministic manner. For example, a study by Emmett & Rabinor (2007), during therapy found that the use of scientific methods alone was not sufficient to treat patients suffering from eating disorders, including food rehabilitation, rebuilding self-esteem and cognitive restructuring, which cannot be accounted for by scientific methods. Emmett and Rabinor conclude that the best form of treatment is a holistic one that incorporates a number of therapies. In addition, anorexia nervosa and bulimia nervosa, for example, are not purely eating disorders, concerning food and appetite; it is also the case that many sufferers suffer from some form of depression (Emmett & Rabinor, 2007; Little & Hoskins, 2004). In determining cause and treatment of psychological disorders one cannot be deterministic, otherwise vital information can be missed and subsequently patients could be harmed. It is the case that psychology should not be deterministic if it wishes to search for the truth and be able to effectively treated individuals. It should also be mentioned that although psychology does take deterministic perspectives in attempting to predict behaviour, behaviour itself cannot always be predicted (Friedenberg & Silverman, 2006; Silverman, 1993; Valentine, 1982). In this sense, psychology should not be or become a science because if it were to limit itself to a purely scientific approach much information would be ignored and consequently psychology would do an injustice to society.
Within psychology there is a great deal of separation between the various fields/perspectives, each field/perspective finding problems with their rivals, which is becoming evermore counterproductive for the pursuit of understanding human behaviour, experience and the mind (Sternberg & Grigorenko, 2001). Furthermore, it is alarming that psychology is becoming increasingly fragmented, reducing any chances of a unified discipline, which searches for the whole truth (Sternberg, 2005).
For example, this is seen in models of aggression (Volavka, 1995). Zillmann et. al. (1978) argues that arousal, regardless of origin, increases the likelihood of aggression, compared to that of Weinshenker & Siegel’s (2002) model of aggression which states that aggression can be seen as defensive or predator affective states, or that of Bandura et. al.’s (1977, as cited by Gough & McFadden, 2001) social imitation theory.
Another example of this can be seen in the differences between behaviourism and psychoanalysis (Medcof & Roth, 1979). Behaviourism rejected measuring cognition or mental states. An extreme behaviourist position even denied the existence of cognition or internal mental states within the field of psychology. Behaviourism investigated objective behaviour, theorising that behaviour is merely a stimulus-response mechanism. Hence, according to behaviourism, we can understand behaviour as responding to cues within the environment (Hirschorn, 1979, as cited by Medcof & Roth, 1979; McLeish, 1963; McGhee, 2001). This can be seen as psychology’s attempt of becoming more scientific in its study of human behaviour. Psychoanalysis, on the other hand, studied the individual’s upbringing, their attachment relationships with their parents, especially their mother and the effect this had upon the development of the individual’s psyche. Thus, the differences between these two approaches in psychology are glaringly obvious. Behaviourism proposes that there is no such thing as cognition, or at least psychology should not be concerned with abstract, subjective mental states, whereas psychoanalysis deems the importance of the psyche/cognition in the influence of human and animal behaviour. (Hirschorn, 1979, as cited by Medcof & Roth, 1979; McLeish, 1963; McGhee, 2001). Therefore, these two approaches oppose one another, thus such doctrinally opposing perspectives could never be unified under one single theory or paradigm. However, according to Glassman (1979, as cited by Medcof & Roth, 1979), behaviourism led to a single body of theory, thus attempting to unify psychology under one all encompassing theory. However, due to its failure, it can be claimed that the different perspectives within psychology cannot be united under one theory. Psychology should therefore, be considered as fragmented and, at present, fundamentally incompatible with regards to the approaches. It is therefore psychology, as a whole, is not unified under one all-encompassing theory and so cannot be considered a science.
Until psychology can incorporate the multifaceted dimensions of its subject matter, psychology cannot become unified in its pursuit of knowledge. Thus, this suggests that psychology is not a science due to its lack of unity and implies that psychology will never become a science in the future. A leading paradigm/perspective does not exist in psychology, as of yet, however, there are numerous different perspectives, some mentioned above, all struggling to become the leading approach and many ways of analysis, such as the experimental/scientific method, all struggling to be the leading paradigm.
Rather than striving for psychology to become a true science, psychologists should focus on creating a more informed, holistic discipline that encompasses the true nature of human behaviour and experience, dropping ideals of science and aspirations of scientific credibility (Bem & Huib, 1997). Truth through a complete understanding of human behaviour will give psychology the credibility it desires.
In conclusion, after attempting to delve into many different areas of the discipline, certain perspectives with psychology can be seen as attempting to be scientific in their approach and methodology, however, other perspectives do not adhere to such scientific procedures. Thus, due to its subject matter, psychology cannot be considered a science and should not become a science, as subjective experience cannot be measured purely in an objective manner. Psychology, if it is to reflect true human behaviour and experience/cognition, needs to become unified and holistic in its approach to the study of humans and animals. Combining scientific and non-scientific methods should be the way forwards for better understanding and truth (Parker, 1994).
Banister, P., Burman, E., Parker, I., Taylor, M. & Tindall, C. (1994). Qualitative Methods in Psychology: A research guide. Buckingham: Open University Press.
Bem, S. & Huib, L. J. (1997). Theoretical Issues in Psychology: An Introduction. (2nd ed). London: Sage.
Burr, V. (1998). Gender and Social Psychology. London: Routledge.
Burr, V. (1995). An Introduction to Social Constructionism. London: Routledge.
Elliot, A. (1999). Social theory and psychoanalysis in transition: self and society from Freud to Kristevo. London; Free Association.
Elliot, A. (1994). Psychoanalytic Theory: An Introduction. Blackwell.
Emmett, S. W. & Rabinor, J. R. (2007). The Therapist’s Voice: The Sated Starver. Eating Disorders: The Journal of Treatment & Prevention. Vol 15(1), 81-84.
Freud, S. (1933). New Introductory Lectures on Psychoanalysis: translated and edited by Strachey, J. (1989). London: W.W. Norton & Company.
Friedenberg, J. & Silverman, G. (2006). Cognitive Science: An Introduction to the Study of Mind. London: Sage.
Frosh, S. (1999). The politics of psychoanalysis: an introduction to Freudian and post-Freudian theory. Basingstoke: Macmillan.
Frosh, S. (1997). For and against psychoanalysis. London: Routledge.
Gough, B. & McFadden, M. (2001). Critical Social Psychology: An Introduction. Palgrave: Basingstoke.
Harre, R. (1989). ‘Language games and the texts of identity’ in J. Shotter & K. J. Gergen (eds), Texts of Identity, London: Sage.
Hepburn, A. (2003). An Introduction to Critical Social Psychology. SAGE: London
Horrocks, R. (1995). Male myths and icons. London: Sage.
Kuhn, T. S. (1962). The Structure of Scientific Revolutions. Chicago: Chicago University Press.
Le Bon, G. (1895, trans. 1947). The crowd: A study of the popular mind. London: Ernest Benn.
Little, J. N. & Hoskins, M. L. (2004). “It’s an Acceptable Identity”: Constructing “Girl” at the Intersections of Health, Media and Meaning-Making. Child & Youth Services, Vol 26(2), 75-93.
McGhee, P. (2001). Thinking Psychologically. Hampshire: Palgrave.
McLeish, J. (1963). The Science of Behaviour. London: Barrie Books Ltd.
Medcof, J. & Roth, J. (eds) (1979). Approaches to Psychology. England: Open University Press.
Popper, K. R. (1972). Conjectures and refutations: the growth of scientific knowledge (4th ed). London: Routledge & Kegan Paul.
Popper, K. R. (1959). The logic of scientific discovery. London: Hutchinson.
Reicher, S. D. (1996a). ‘The Battle of Westminster’: Developing the social identity model of crowd behaviour in order to explain the initiation and development of collective conflict. European Journal of Social Psychology, 26, 115-134.
Reicher, S. D. (1984). The St. Paul’s riot: An explanation of the limits of crowd action in terms of social identity model. European Journal of Social Psychology, 14, 1-21.
Richards, G. (1996). Putting Psychology in its Place: An Introduction from a Critical Historical Perspective. London: Routledge.
Silverman, D. (1993). Interpreting Qualitative Data. Methods for Analysing Talk, Text and Interaction. London: Sage.
Sternberg, R. J. (2005). Unity in Psychology: Possibility or Pipedream? London: American Psychological Association.
Sternberg, R. J. & Grigorenko, E. L. (2001). Unified Psychology. American Psychologist, 56, 1069-1079.
Valentine, E. R. (1982). Conceptual Issues in Psychology. Hemel Hempstead: George Allen & Unwin (Publishers) Ltd.
Wetherell, M. & Maybin, J. (1996). Mapping the Language of Racism: Discourse and the Legitimatising of Exploitation. Hemel Hempstead: Harvester Wheatsheaf.
Willig, C. (2001). Introducing Qualitative Research in Psychology: adventures in theory and method. Buckingham: Open University Press.
Zimbardo, P. (1969). The human choice: Individuation, reason and order versus deindividuation, impulse and chaos. In W. J. Arnold & D Levine (Eds.). Nebraska symposium on motivation. Vol 17. Lincoln, NB: University of Nebraska Press.