Where Do the Main Approaches in Psychology Stand on Determinism?

Where do the main approaches in psychology stand on determinism?

The biological approach takes the view that behaviour is determined by internal, biological systems. This is physiological determinism. Up to a point physiological determinism is a valid argument. Clearly physiological factors provide explanations of behaviour but do they offer a complete explanation? They may be more applicable to non-human animals where learning has less influence on behaviour. Non-human animals also lack the ability to be self-reflective, as demonstrated by their lack of self-awareness, which is associated with the concept of “will”. Without self-awareness and consciousness, can an organism be said to have a will?
The behaviourist approach proposes that all behaviour is learned and can be explained solely in terms of external (environmental) factors. This is environmental determinism. Skinner said that freedom was an illusion, maintained only because we are unaware of the environmental causes of behaviour. This gives us an answer to the dilemma: “But I have a personal sense of free will”—the response from behaviourists is that what you experience is an illusion.
The cognitive approach is mechanistic, and any mechanistic explanation is determinist because it suggests that a particular action will result in a predictable result.
The psychoanalytic approach suggests that adult behaviour or personality is predetermined by events in early childhood. This is called psychic determinism because the causes of our behaviour are psychological and not freely chosen. Freud, like Skinner, believed that free will was an illusion. Freud believed this was because the actual causes of our behaviour are unconscious and therefore hidden from us.
However, Freud also believed that people have some potential for free will—psychoanalysis is based on the principle that people can change. Freud proposed the principle of “overdetermination”, that behaviour has multiple causes some of which are conscious and these would be subject to free will.
The evolutionary approach is highly deterministic. A fundamental assumption of the evolutionary approach (genetic determinism) is that physical and psychological characteristics are inherited. This must be so because it is only inherited characteristics that can be naturally selected and passed on to the next generation. This means that the evolutionary approach is a highly deterministic one, though this may be less true as one moves up the evolutionary scale and cultural evolution has a greater effect on behaviour.
The humanistic approach embraces free will. Rogers believed that humans have an innate drive towards positive growth and self-actualisation. Individuals who deny aspects of themselves are unable to do this. If one disowns a part of one’s behaviour (“That’s not like me to do such a thing”) then that behaviour is not part of one’s self-concept and therefore cannot be controlled. Your behaviour is then not self-determined. Healthy psychological development and adjustment depend on “owning” all of your behaviour. In this way you are exercising free will, and are able to reach your full potential. In addition to this, the humanistic approach stresses the responsibility each of us has for our own actions. Rather than seeking explanations for our behaviour in terms of other influences, each of us must accept the moral responsibility for our actions. This is a fundamental issue for questions of adult legal responsibilities.