Your impact on reality depends on your ability to influence yourself, and others. Influence only works within people's existing goals and motivations. So let's start by looking at the motivations that drive all human behavior.

What is the goal of life? Survival.

Why survival? Life is a continuous process of experimentation to create genes that survive. We exist because our genes are fine-tuned for survival. We're survival machine built by our genes.  

How does this explain human behavior? We can trace all behavior back to the basics of survival, stay alive and reproduce. But, there's another piece for distinguishing humans from animals.

We build advanced tools. We build mental tools to better understand reality. And, physical tools to better control the environment. Our best mental tool is our use of stories to communicate ideas and organize groups.

Tools accelerate progress, but progress can be negative, or have negative side-effects. It takes time to solve these new problems. Our recent progress still has many unsolved problems. This is why we see many people behaving counter to their survival.

With this model of human behavior, what impact should we aim to have? Align your behavior with survival. Find, create, use, and spread tools that improve survival. Take careful consideration of the risks and trade-offs.