INITIALLY needs to be introduced when demonstrating how psychologists use experiments in the COGNITIVE approach; taking a scientific approach necessarily involves reductionism ; whittling down possibilities to get closer to the truth through the process of hypothetico-deductive reasoning.

Also comes in to SOCIAL approach when talking about Latane using mathematical formula f(SIN) to calculate and predict social impact.

Also comes into LEARNING when discussing the absence of biological and cultural factors in the conditioning theories

What is reductionism?

The experience of being a human and thus the study of the human mind and behaviour is a complex area and the phrase reductionism refers to the act of breaking a complex phenonema into its constituent parts. Those who believe in reductionism believe that it is helpful to do so. For example, Morgan’s Law of Parsimony states that “we have no need to explain behaviour in terms of complex psychological processes when it can be explained adequately in terms of much simpler processes”, (Cardwell, et al, 2004).

Both theories and studies can be reductionist as exemplified by the terms “Reductionism in explanations” and “methodological reductionism“.

Reductionism in explanations

Research sometimes confuses ultimate (original causes) and proximal causes (here and now) , for example biological research looking at the role of dopamine as a determinant of schizophrenic symptoms may only look at proximal causes and fail to recognize the ultimate cause of the excessive dopamine levels, for example these theories tend to fail to examine the role of cognition in terms of the way in which people reason about stressors in their lives, e.g. “this set of circumstances will stop me achieving what I need to do; this is situation is therefore a problem…and it’s insurmountable”; this way of thinking will cause stress, which may affect the production of specific neurotransmitters and therefore the cognitive style is the ultimate cause of the problem and this should therefore be addressed in treatment ; think about CBT in schizophrenia and the case of Carol.

Methodological reductionism

The scientific method is reductionist and the nomothetic approach which focuses on the development of universal laws which determine behaviour through the collection of quantitative data are also reductionist.

For reductionism

Reductionism, through the use of the scientific approach, allows causal relationships to be unveiled and this allows us to accurately predict outcomes in specific situations, this is clearly of benefit to society.

Against reductionism

Reductionsism and the nomothetic approach contrast with the idiographic approach which focuses on the uniqueness of the individual and his or her experience of the world. Researchers from this epistemological background prefer to collect qualitative data, through observation and interviews for example, to understand the differing versions of “reality” that are constructed at the individual and group level. This approach is holistic as opposed to reductionist and recognises that the pursuit of universal truths may be a fruitless enterprise.

Many people use the term reductionist as a criticism, meaning that when we look at how individual parts interact with each other we may fail to understand the system as a whole.

The scientific method is reductionist in itself as we isolate individual independent variables and examine how they affect dependent variables. However, the reality is that many experiments in fact have more than one IV and use statistics to help them to look at interactions between IVs and also to work out how much of the variance in the DV is attributable to each IV.


  • Linear models such as the multi-store model of memory are reductionist and more recent models of memory that focus on neural networks and connectivity may be considered more helpful. These models suggest that the memory system is made up of many inter-connected neurons and say that properties may emerge from the network which are not as simple as the sum of the individual parts. This relates to an area of work know as Gestalt Psychology, gestalt is a German phrase linked to holism which essentially means “the whole is greater than the sum of its parts.
  • Cognitive research into memory such as Peterson and Peterson (1959) required Pps to remember trigrams which are deliberately meaningless in an attempt to standardise prior knowledge, which could have reduced the validity of the conclusions; however, this operationalisation of the DV arguably removed it so far from the reality of remembering things that the study findings become relatively meaningless; this example of methodological reductionism demonstrates that despite the advantages that the scientific methods can bestow it can also be detrimental to our pursuit of the truth in real world situations.
  • The use of case studies in cognitive psych is good as method triangulation using both qual and quan and primary and secondary data removes the reductionist tendency of work which is purely experimental.


  • Social Impact Theory: predicts behaviour using a mathematical equation
  • Questionnaires: reduce attitudes and values to number and categories
  • Milgram: collected qual data which helped to explain the more reductionist quan data he gathered;
  • Sherif: method triangulation helped protect against reductionism


  • breaking behaviour down into individual stimulus/response units is reductionist; how often in real life are we faced with single stimuli which no other contextual details that might over-ride and mediate the biological response which is elicited
  • with regard to classical conditioning, focusing purely on biological reflexive behaviours may well be advantageous from a scientific point of view due to the objectivity or empirical nature of behaviour as opposed to cognition and/or feelings however, the reality is that many behaviours are mediated by cognition, that is, we think about how to respond and how our behaviour might impact other people and their perception of us etc.
  • operant conditioning is also reductionist as it fails to consider the impact of cognition and social and cultural norms with regard to dictating whether certain consequences are likely to be positively or negatively reinforcing or indeed punishing.


  • the use of animals in psychology stems for the idea of evolutionary continuity, that is that studying more simple behaviours in animals is useful for understanding more complex behaviours in humans as humans are just a little further long the evolutionary path; differences between us and other animals are quantitative not qualitative. This idea helps to justify reductionism in biological psychology at least.
  • However, this idea fails to recognise the impact of the environment on the human brain as demonstrated in studies of plasticity.


  • Biological models of depression and schizophrenia prevail as it is fairly easy to alter levels of various neurochemicals using drugs and to explore localisation of brain function through lesioning and ablation for example in animals;
  • these techniques have allowed us to understand how abnormalities of the nervous system are linked to abnormalities of behaviour;
  • however this has led to a reductionism in clinical psychology in the understanding of disorders and also in their treatment;
  • it is not so easy to explore the impact of long term exposure to poverty, neglect or discrimination for example in the laboratory or through the use of animals models and this means a more holistic view of how social, cultural and cognitive factors affect biology has been somewhat over-looked.
  • This said, the work of Miller (1977) who replicated Seligman’s dogs has some very interesting implications which are more holistic than either a simple biological or behaviourist approach could have provided.
  • Laing argues that studying schizophrenia at the chemical level entirely misses the point and says it should only be studied at the level of experience of the individual; he says that treatment should also target this level of understanding; what are your thought on this suggestion? What do you know about the effectiveness of drug treatments for example?


Focuses on individual uniqueness and rejects reductionism as a “way of knowing”.

Assessment Task: 

Old SAMS: Evaluate the issue of reductionism in relation to the use of biological and learning theories in explaining human behaviour (12)

Mark Scheme: See SAMs for mark scheme

June 2017: The first A Level exam had a question on Reductionism