The most widely accepted definition of psychology is that it is the scientific study of behavior and mental processes. The emphasis on scientific has been there from the 19th century, which indicates that, largely, psychology follows the scientific methods and principles. One such principle has been the doctrine of determinism. The doctrine of determinism is the assumption that all that is investigated is lawful, that is, it can be understood in terms of causal laws.
Determinism, in psychology, is the assumption that all behaviors have a specific cause. In other words, determinism centers around the notion of causation. Determinists have the assumption that all the events in the universe have a cause. Further, since human beings are part of the universe, all human behaviors also have a cause. The assumption of determinism also suggests that all the causes of behavior are beyond the control of human beings. This suggests that, according to determinism, human being have no control over their own behavior.
The idea of human behavior being deterministic fits well with the notion of science and scientific psychology. Determinists believe that the more causes of behavior are known, the easier it will be to make prediction about human behavior.
Spinoza suggested that the laws of nature are applicable to the mind and other psychological processes. He further suggested that these laws can be used to study psychological processes. The strict deterministic perspective of Spinoza led to the rise of the scientific investigation of the mind. It turned out to be an important precursor to scientific psychology. It eventually played an influential role in Gustav Theodor Fechner and Wilhelm Wundt in introducing the experimental approach to the discipline of psychology.
Apart from Spinoza, one of the earliest modern thinkers to talk about lawfulness of psychological processes and assert a deterministic perspective of human behavior, is the founder of British empiricism, Thomas Hobbes. Hobbes was highly influenced by Galileo, the father of modern physics. Galileo had explained the motion of physical objects using the mechanistic principle, suggesting that external forces act upon them.
Hobbes felt that human beings are also part of nature, and thus, human behavior can also be explained as the motion of physical objects, that is, by the mechanistic principle. This was the first serious attempt to explain human behavior by using the techniques of Galileo, that is, it began the use of the methods of the physical sciences in examining human behavior. Because Hobbes was convinced that the motion of physical objects is caused by external forces acting on them, and that human behavior can be explained in the same way, he was using a deterministic perspective.
The deterministic perspective of Hobbes was carried forward by the later British empiricists, which eventually laid the foundation of scientific psychology that was established by Wilhelm Wundt. Therefore, Spinoza and Hobbes, being two of the earliest thinkers that used a deterministic perspective in understanding human behavior, were instrumental in making the discipline of psychology scientific in nature. It was their deterministic view of behavior that made psychologists during the beginning of modern psychology to also believe in determinism.
The belief in determinism by the early psychologists can be clearly found in the ideas of the five classical schools of psychology – structuralism, functionalism, psychoanalysis, gestalt psychology, and behaviorism. Structuralism, the first school of psychology, emphasized on the experimental method, suggesting investigation in terms of causal relationships. It also has been known to rigidly follow the mechanistic principle. This makes the school of structuralism deterministic in nature.
The school of functionalism emphasized on adaptation to the environment. According to functionalism, consciousness helps individuals to adapt in the environment; the environmental forces are acting upon the mind. This main idea of functionalism makes it deterministic.
The school of psychoanalysis emphasizes on the unconscious mind and childhood experiences shaping adult behavior. Individuals, according to psychoanalysis, have no control over their behavior. This makes the school of psychoanalysis to be deterministic in nature.
Gestalt psychology emphasizes on universal laws that govern perceptual organization and information processing. It suggests that the mind organizes and interprets information in a lawful manner. This indicates that the school of gestalt psychology is also deterministic in nature.
Finally, the school of behaviorism can be arguably viewed as the most deterministic among the five classical schools of psychology. Behaviorism is highly mechanistic in nature. It suggests that human beings passively respond to stimuli in the environment. Behaviorism strongly emphasizes on causal relationships – the stimuli causing a behavioral response.
The five classical schools of psychology being deterministic can be viewed as a direct consequence of modern psychology emphasizing on using the scientific methods. This trend was found in most of the subfields in psychology that emerged in the later years.
Determinism in psychology can be broadly classified as physical determinism and psychical determinism. When the cause(s) of behavior is measurable and quantifiable then it is referred to as physical determinism. Physical determinism includes biological, environmental, and socio-cultural determinism.
If the causes of behavior are related physiological processes or genetics, then it is said to be biological determinism. If the causes of behavior are environmental stimuli, that is, it lies within the environment, and outside the individual, then it is said to be environmental determinism. If the causes of behavior are related to socio-cultural processes such as culture, norms, and customs, then it is said to be socio-cultural determinism. In all of these cases, the causes of behavior can be directly measured and even quantified. Psychologists who are involved in biopsychology, environmental psychology, behavioral theory, social psychology, cultural psychology, etc. are all associated with physical determinism.
In contrast to physical determinism, when the cause(s) of behavior are subjective in nature, and cannot be directly measured, then it is known as psychical determinism. It mainly includes causes explained in terms of cognitive and emotional experiences. If the causes of behavior are beliefs, emotions, perceptions, ideas, etc., then it is said to be psychical determinism. The psychologists giving emphasis to conscious, non-conscious, and unconscious mental events, such as those who are involved in cognitive psychology, or psychoanalysis are associated with psychical determinism.
Both physical and psychical determinism, thus, cover up most of the subfields in the discipline of psychology, in contemporary times. This indicates that the idea of determinism has been widely accepted within psychology.
Despite its wide acceptance, however, psychologists have often had to face one major criticism when associating determinism with human behavior. Human behavior being deterministic automatically gives the idea that human beings have no control over their behavior, and that their behavior is guided by forces that are beyond their control. This idea of human behavior has been suggested to be very dangerous by many scholars, and even raises a number of moralistic issues. Scholars against the idea of determinism argue that without having any personal responsibility over their behavior, human beings can get away with the most heinous acts by simply suggesting that everything is deterministic.
In this regard, James differentiated between what he called hard determinism and soft determinism. When the behavior is caused by automatic or mechanistic processes, then it is called hard determinism. In such cases there will be no personal responsibility.
Soft determinism, on the other hand, involves cognitive processes such as intention, motivation, beliefs. These are rational processes that occur due to deliberate thought. They qualify as causes of behavior, but individuals have a choice to act in a specific way. Therefore, soft determinism becomes a way for personal responsibility to be associated with determinism.
Irrespective of personal responsibility, the one thing that all psychologists agree upon is that determinism with respect to human behavior becomes very complicated. Psychologists suggest that there can be a number of causes behind one specific behavior. This makes it very difficult to specify exactly what has caused a specific behavior. A lot of times a number of behaviors even occur accidently or suddenly or unexpectedly. This further makes determinism complicated in human behavior, because even when there is a cause, it becomes almost impossible to make predictions.
Psychologists have also borrowed the idea of the uncertainty principle from physics, in giving the argument of determinism being complicated with respect to human behavior. The physicist Karl Heisenberg, who gave this principle, suggested that simply observing an object/phenomenon can affect its activity, creating doubts about the validity of the observation. This indicates that nothing can be known with certainty, thus, known as the uncertainty principle.
The same idea when applied to human behavior suggests that the cause of any behavior cannot be certain. Determinists in psychology feel that even though behavior has specific causes, the uncertainty principle suggests that there can be no certainty about knowing those causes. Therefore, determinism or the idea of causation with respect to human behavior becomes very complicated.