I am of the opinion that you only ever own 2 things in this world: Your thoughts and your behavior.
You need both to live, but both govern each other in a way that’s sometimes too subtle to realize. It’s like the check and balance system of the mind and body.
If you find your thoughts clouded, try changing your behavior. Your thoughts may follow. If you find your behavior consistently at odds (in a dangerous way) with the reality around you, try a different perspective. Your behavior may follow.
Here’s an exercise to try: If you’re in your car today, stop for every pedestrian you see waiting at a crosswalk and watch them. It’ll help you figure out a way to get cars to stop for you when you’re a pedestrian.
I agree: perception is what we’re given for free-will (you choose how to feel, and how to react).