Behavioural psychology makes some assumption that humans are rational and that a solid marketing and education strategy as to why it is worth changing behaviour will ultimately drive change.
“If we all make systematic mistakes in our decisions, then why not develop new strategies, tools, and methods to help us make better decisions and improve our overall well-being?” Dan Ariely
Behavioural economics has a focus on driving action, and ensuring there is a strong focus on reinforcing such behaviour. Behavioural economics determines strategies to overcome irrationality and other entrenched barriers to change
Heuristics help explain why we make irrational decisions on a day-to-day basis. They are experience-based techniques for problem solving, learning and discovery. People often make decisions based on approximate ‘rules of thumb’ and ‘mental shortcuts’ rather than being totally rational.
For example ...
Incentives: Our response to incentives are shaped by predictable mental shortcuts such as strongly avoiding losses; Defaults: We 'go with the flow' of pre-set options; Priming: Our acts are often influenced by sub-conscious cues; Commitments: We seek to be consistent with our public promises, and reciprocate acts; Ego: We act in ways that make us feel better.