Consider a standard definition of philosophy:
Philosophy: the rational investigation of the truths and principles of being, knowledge, or conduct.
Physicians certainly are investigators who seek both physical and mental truths.
We are also students of two aspects of being: life and death.
And we are familiar with the strengths and limitations of the different types of knowledge acquisition—such as cohort, cross-sectional, and case-controlled studies.
Finally, we understand how personal and public conduct can impact a person’s well-being.
This does not mean the practice of a physician is the same as the practice of philosophy (and therefore being a philosopher).
But the step from a physician to a philosopher is much shorter than we think.