Psychological perspectives
Different psychological perspectives have different types of theories which try to explain human behaviour. There are several theories which are all different from each other but they share common assumptions. Most psychologists agree that none of the theories are correct, and they all have weaknesses as much as their strengths, but they all bring different ways to be able to understand human behaviours. In early years of psychologist would believe that behaviourist perspective was the only true one because it could be proved scientifically. So in my work I will explain all of the different perspectives towards behaviour, and also talk about their strengths and weaknesses.

Behaviourist perspective
Behaviourists believe that humans act the way they are because of what they have learnt due to an experience.
The Behaviourist perspective argues that in order for psychology to be scientific they should focus on behaviour which is observable behaviour which is measurable objectively rather than cognitive process which can only be inferred. There are two learning theories which psychologist has discovered “classical conditioning” (Pavlov) is and “operant conditioning” (Skinner). The experiments show how reinforcements shape behaviour.
Behaviourism also believes in scientific methodology (e.g. controlled experiments), and that only observable behaviour should be studies because this can be objectively measured. Behaviourism rejects the idea that people have free will, and believes that the environment determines all behaviour. Behaviourism is the scientific study of observable behaviour working on the basis that behaviour can be reduced to learn S-R (Stimulus-Response) units.

( A paragraph from this site - http://www.simplypsychology.org/perspective.html )
Classical conditioning Pavlov
Pavlov Ivan a Russian physiologist was studying digestion in dog in the early 1900s he was measuring how much dogs were salivating in different circumstances, the researcher then realised that the dogs started to salivate when they started to hear his footsteps approaching.
“it occurs automatically when associate the sound of footsteps with the arrival of food because the two stimuli had occurred together so many times” << Understanding psychology Second edition Barbara Woods Published august 2004 ISBN- 978 0 340 88668 7

Pavlov predicted that if another stimulus was introduced with the dog and the food the dog will then become associated with this stimulus and start to salivate. With this idea Pavlov began his experiment and started to present the dog with a bell and started to ring it (conditional or neutral stimulus) he then presented the food at the same time as the food. The dog continued to salivate to only when he saw the food which was an involuntary reflex. After a certain number of experiments Pavlov started to discover that the dog had began to respond to the bell and salivate before he seen the food, so he knew when the food was coming and had learnt this. Pavlov had referred to the association as a conditional reflex.

Stage 1 before learning
Unconditioned stimulus Unconditional response (food) (salivation)

Stage 2 during learning
Unconditional stimulus + Conditioned stimulus Unconditional response (food) (bell) (salivation)

Stage 3 after learning