The Basic Idea

Functionalism is a psychological philosophy that describes the mind as a functional tool that allows us to adapt to our environments. It posits that our mental states and behaviors are survival mechanisms, in line with our inherent biological goals. Sound like evolution? That’s because functionalism, or functional psychology, stems directly from Darwin’s school of thought, emerging in the late 19th century as a counter  to the prevailing theory of structuralism. Unlike structuralism, which tries  to simply understand our subjective experience of consciousness, functionalism also aims to find meaning and purpose in what we experience.

The greatest discovery of my generation is that a human being can alter his life by altering his attitudes.

– William James, American Psychologist

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Key Terms


An approach to psychology that analyses mental states and behaviors in terms of their purposes, placing an emphasis on the broad capability of the human mind. Functionalism marked a major departure from conventional ‘structuralist’ ideas in psychology from the 19th century onwards.


The precursor to  functionalism, which advocates for an ‘introspective’ approach to psychology, focusing on understanding the individual structures that make up our consciousness.

Evolutionary Psychology

A strand of psychology that considers our mental processes, emotions and behaviors as strategies we use in order to adapt to and survive in our environments.


The origins of functionalism are traced back to William James, the renowned American psychologist of the late 19th century.1 James was heavily influenced by Darwin’s theory of evolution, and was critical of the structural approach to psychology that had dominated the field since its inception. James argued that instead of focusing on the specific ‘introspective’ elements that make up our consciousness, psychology should consider the purpose of consciousness, psychological states, and behavior.

Although James is credited as being the first to advocate for a functional approach to psychology, the school of functionalism itself did not fully emerge until later in the 19th century, when scholars at the University of Chicago began to formalise the theory. It was here that John Dewey, Harvey A. Carr and James Rowland Angell would all develop functionalism, focusing especially on the biological and animal dimensions of learning and behavior. Another group of functionalists would emerge in Columbia University, most notably Edward Thorndike. Thorndike’s  work on reinforcement theory and behavior analysis provided the basis for the empirical laws that emerged under behaviorism later in the 20th century.2

As functional psychology developed, so too did the field of experimental psychology. Most functionalists of the early 20th century also pioneered novel techniques in lab and field analyses of human and animal behavior. The experimental method in psychology has led to major breakthroughs in our understanding of the functional organization of our brains, as psychologists continue to use experiments to manipulate certain variables that may explain our behavior.


William James

Often considered the father of American psychology,  James was  one of the first to advocate a functional approach to the field. William James was a Harvard Professor and leading thinker of late 19th century America.

Edward Lee Thorndike

Thorndike’s research of animal behaviour and the learning process led to the law of effect which states that, through a process of trial and error, subjects find the most satisfying behavioral responses to specific stimuli, and these become their most used responses in the future.

John Dewey

American philosopher, psychologist, and educational reformer, Dewey’s 1896 paper “The Reflex Arc Concept in Psychology” is considered the first major work of functionalism.

Harvey Carr

Carr was an American psychologist and Chairman of the University of Chicago’s Psychology Department (which had become the hub of the Functionalist movement) between 1926-1938. He is best known for the Kerplunk Experiment, a famous stimulus and response test conducted on rats, which he ran with John Watson.


Functionalism had an important influence on the trajectory of psychology from the 19th century onward. Once  functionalism took off, most structuralist ideas – which had previously dominated the field – were disputed and didn’t make their way into the modern psychology we know today. Most notably, functionalism led directly to the emergence of behaviorism in the mid 20th century, which views human behavior as a type of ‘reflex’ in response to external stimuli.

Famous behaviorists including B.F. Skinner and Iain Pavlov based many of their ideas around reinforcement learning and conditioning on the findings of functionalists.  You’ve likely heard of Pavlov’s famous classical conditioning experiment in which he conditioned dogs to salivate at the sound of a bell. That probably wouldn’t have happened without functionalism, which was the starting point for studies that considered our mental processes and behaviour as responses to external stimuli. The field of behaviorism and its practical application in Applied Behavior Analysis (which uses empirical approaches to encourage positive behaviour) would go on to become a hugely popular philosophy in clinical psychology, and continues to be used today as an intervention for people with conditions such as autism, dementia and addiction.3

Functionalism also had a direct influence on the education system in the US. This was largely due to John Dewey’s theory that children should learn at the pace that best suits their level of intellectual development, and that the curriculum should encourage students to draw from their own interests and experiences.1 Functionalist and behaviorist ideas are also used in special education settings as tools for  positive behavior support.

Finally, the experimental tradition that grew up alongside functionalism brought a wide range of research methods that are still used in modern psychology today. These include observation studies, physiological measures, mental tests, and questionnaires.


Functionalism is sometimes considered the bridge between early structuralist-based ideas, and modern behaviorism. Naturally, it has received criticism from both schools of thought.

At first, structuralists argued that functionalism did not fully define or attempt to understand the mental processes they were dealing with. Instead of trying to explain mental states and behaviors in the context of environmental stimuli, structuralists believed that psychologists should focus on introspection and understanding these aspects of consciousness for what they are. They also argued against the applied nature of functional psychology, believing that it distracted from the core goal of identifying the structures of consciousness.

Behaviorists in the mid-late 20th century would also take issue with some aspects of functionalism. While functionalists believed it was important to accept the role of consciousness and internal cognitions such as pre-existing beliefs, behaviorists were only concerned with the study of human behavior, and rejected any idea that did not view mental states as directly influenced by external  stimuli.4

Case Study

Functionalism and Beliefs

We all hold personal beliefs, often based on experience or knowledge, things we learned ourselves, or picked up from other people. A functional approach to beliefs would argue that beliefs are designed to serve a particular purpose and help us achieve specific goals. Researchers have explored a broad range of beliefs from this perspective. For example, holding the belief that we have something in common with a group allows us to ‘fit in’ better. Having a positive self-image helps us protect our egos, and believing that a particular situation could be risky (e.g. driving under the influence of alcohol) prevents us from causing harm to ourselves and others.6

Beliefs can be surprisingly accurate, and humans make thousands of useful decisions a day based on subconscious beliefs. For example, when you press the ‘on’ button on your remote control, you do so with the belief that it will cause the TV to turn on. That said, many of our beliefs come from deeper cognitive processes, like biases and heuristics. For example, we might believe that a beauty product is guaranteed to make us look 10 years younger, simply because it was mentioned in the first review we read (see the anchoring bias). Granted, these types of beliefs can get us into trouble from time to time, but functionalists will argue that they still do serve a purpose. In this case, we probably get short-term pleasure from the idea that we could look younger, as well as the fact that we didn’t need to spend much time reading to get the answer we wanted!

Related TDL resources

Why do we tend to think that things that happened recently are more likely to happen again?

Sometimes our beliefs are biased based on how available they are to us in the moment. Check out the availability heuristic to understand how this happens, and how it can skew our decision making.

Why do we look for consistency in our beliefs?

Cognitive dissonance occurs when our beliefs and our behavior don’t align, often leading to internal dilemmas.


  1. Encyclopedia Britannica. (2021). Functionalism | psychology. Retrieved 15 February 2021, from
  2. How Structuralism and Functionalism Influenced Early Psychology. (2021). Retrieved 15 February 2021, from
  3. Morris, E. K., Altus, D. E., & Smith, N. G. (2013). A study in the founding of applied behavior analysis through its publications. The Behavior Analyst36(1), 73-107.
  4. Stanford Encyclopedia of Philosophy (2021). Functionalism.  Retrieved 15 February 2021, from
  5. Cummins, R. (1975). Functional explanation. Journal of Philosophy72, 741-764.
  6. Boden, M. T., Berenbaum, H., & Gross, J. J. (2016). Why do people believe what they do? A functionalist perspective. Review of General Psychology20(4), 399-411.

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