The term psychological science refers to the accumulated body of psychological knowledge (i.e., pertaining to brain, behavior, social, or mental processes) that has been generated through the systematic application of the scientific method.
Scientific means that things have been tested out and proven to be accurate. There are Scientific things related to psychology because psychologists also study neurons, nerves, etc.
Behaviors are related habits, movements , speech, etc and they are all apart of the brain and that’s what psychologists study
I have no idea what I just typed but I hope it helps -,- you can just build off of it if you feel like it’s accurate
