Here's why:

* Focus on the natural world: Physics studies the fundamental laws and principles governing matter and energy. It deals with topics like motion, forces, heat, light, electricity, magnetism, and the structure of atoms and molecules. This is all part of the natural world.

* Quantitative and objective: Physics relies heavily on mathematical models and experiments to describe and predict phenomena. It seeks to understand the universe through objective observations and measurements.

* Distinct from life and social sciences: While physics can be applied to biological systems (biophysics) or social systems (econophysics), it doesn't directly study living organisms or human behavior. That's the realm of life sciences and social sciences.

Let me know if you have any other questions!