This concept refers to the fact that human behaviour is not a spontaneous and unpredictable process, rather it can be scientifically analysed and pre-empted because humans follow psychological patterns, and most actions we take are the result of a cause-and-effect reaction.
It could be argued that everything we do, every action we take, has a biological or social stimulus - a cause for each action.
In this way, understanding the causes of actions we are likely to commit makes human behaviour somewhat predictable.