What is the reward for seeking worldly knowledge, such as medicine, and what is the correct intention for learning it, and what is the reward consequently entailed?

Worldly sciences upon which the interests of people and the structure of society are built are considered a communal obligation (fard kifaya). Their practitioner is in a state of worship if he intends by his work to fulfill this obligation and serve society, and he will receive a great reward, because he is fulfilling one of the communal obligations, which some scholars have even considered to be superior to individual obligations (fard ayn).