Behavioral Science means applying a multi-disciplinary approach to challenges and opportunities.
In the popularization of behavioral science what has stood out the most has been cognitive biases, systems 1 and 2, and Nudge, meaning more credit around the economics side of things.
Behavioral Science has and should continue to evolve - based on new findings, new ways of approaching challenges, on iteration, testing, and learning and on mixing methodologies.
Robin Schimmelpfennig and colleagues (2023) wrote a paper called Cultural evolutionary behavioural science in public policy where this image is taken from.
As other practitioners and academics have pointed out, the image may be reductionist and not represent the whole evolution, or put more highlight on persuasion or social marketing. I would also say that more recently I see more emphasis on systems science and other areas which are not mentioned either. Nevertheless, it is still good to know that there is an evolution happening and that the authors tried to highlight it.
From my experience as a non academic working on projects that focus on change is that we are trying to give a new perspective on how organizations can use the best levers and look at challenges or opportunites with a new perspective.
That perspective should come from thing like:
-Critical Thinking -Psychology -Anthropology -Sociology -Culture -Systems Thinking -Human Centered Design -Strategic Foresight
It's by mixing methods - and knowing which are out there, that will help us get a stronger hypothesis to test.
For me - this mix of methods is what I call behavior science - (I'm sure some academics will come and correct me) - but what I care about is to help people and organizations make progress towards their outcomes.
My advice to any new person working on change:
-You need to evolve and be curious about other methods that can help your context -You need to go beyond cognitive biases as your go to tool -You need to understand that you can't copy paste strategies and that there are no proven toolkits that will always work for you -You need to know that there is no one model or one framework that rules them all, they can all be helpful if you know how to contextualize them