Social psychology is the scientific study of the effects on social and cognitive processes on the way individuals perceive, influence and relate to others. Social processes are the ways in which input from the people and groups around us affect our thoughts, feelings and actions. Cognitive processes are the ways in which our memories, perceptions, thoughts, emotions and motives influence our understanding of the world and guide our action. Social processes affect us, even when other individuals are not present. The social processes that affect us when other individuals are present depend on we interpret others, thus, including cognitive processes. Social psychology seeks an understanding of the reasons people act the way they do in social situations.

The presence of others often facilitates performance when individual contributions are easily identified, but it reduces performance when this is not the case. Early social psychology rejected the behaviourist view that thoughts, emotions and attitudes did not have to be taken into account when trying to explain behaviour. Social psychology focusses on how external stimuli are interpreted by the individual and how this influences behaviour.

Nazism in Europe influenced social psychology because many gestalt psychologists fled to North America, where a mix between gestalt psychologists and behaviourists was created. The aftermath of the second world war also led to many questions which social psychology had to answer.

Europe’s and North America’s social psychology research integrated with each other and the field started to expand. There was also an integration of cognitive and social processes in the field of social psychology and integration with other research trends. Social psychology research can be applied in education, law, the environment, business and health.

There are two fundamental axioms in social psychology:

1. Construction of reality
   Each person’s view of reality is a construction, shaped both by cognitive processes and by social processes.
2. Pervasiveness of social influences
   Other people influence virtually all of our thoughts, feelings and behaviour, whether others are physically present or not.

There are three motivational principles:

1. Mastery
   People seek to understand and predict events in the social world in order to obtain rewards. People seek to act in ways that appear likely to lead to the most rewarding results.
2. Connectedness
   People seek support, liking and acceptance from the people and groups they care about and value.
3. Valuing ‘me and mine’
   People desire to see themselves and other people and groups connected to themselves in a positive light. People see themselves in a positive light by comparing themselves to others that are worse off.

There are three processing principles:

1. Conservatism principle
   Individuals’ and groups’ views of the world are slow to change and prone to perpetuate themselves.
2. Accessibility principle
   The information that is most readily available generally has the most impact on thoughts, feelings and behaviour. This is related to the availability bias.
3. Superficiality versus depth principle
   People ordinarily put little effort into dealing with information, but at times are motivated to consider the information in more depth.

The eight principles account for all types of social behaviour.