Strengths and weaknesses of reductionism in psychologyWatch
Reductionism is reducing humans into simple forms.
So the biological approach would be guilty of this, as they explain behaviour in simple terms of neurotransmitters and the brain. It's very deterministic, whereas the humanistic approach is the opposite because it considers the whole person. Not single parts of it.
Weakness: If we focus on just one explanation, we cut out other explanations (e.g. focus on biological cuts out that behaviour can be learnt), this is quite damaging as any treatments created may not be accurately treating the correct thing.
Easier to treat that disorder if you're looking at one particular cause only. Eg depression with drugs
Not all of the causes are treated. If you're saying depression for example is solely down to a biological mechanism then you'd only be treating the symptoms of it not the cause of it by using drugs when other treatment methods from other psychological approaches eg CBT would be motor effective treatment in the long term.
It is also an over simplification, human behaviour is very complicated and different things feed into our behaviour it cannot be defined by one approach alone.
You'll find on any mental illness there will be studying findings that support more than one psychological approach, this should show then that there are many psychological explanations. If it were down to solely one approach being the causing factor, there wouldn't be evidence from other approaches.