Is it permissible to look at the private parts of a man or a woman for the purpose of learning?

The basic principle is that it is impermissible to look at the 'awrah (private parts) for both men and women. The Prophet, peace and blessings be upon him, said: "Guard your 'awrah except from your wife or what your right hand possesses." For a medical student, it is generally impermissible to look at the 'awrah of the opposite gender during learning, as there is often no necessity. The fundamental principle is that each gender should specialize in the diseases of their own gender. If necessity or need arises, then one may look at the 'awrah of their own gender. There is no objection to learning about the opposite gender theoretically or practically, as long as it does not lead to committing something forbidden. As for looking under the pretext of learning about the opposite gender, it is impermissible.