Question

how did galen discover more about how the human body worked? what limited galens understanding of the human body?

Explanation:

Galen conducted animal dissections (such as pigs and monkeys) as human dissection was restricted in his time. He also drew on clinical observations of patients. His understanding was limited by the lack of human dissection, which led to some inaccuracies in his theories. Also, the scientific knowledge and technology of his era were not as advanced as today's.

Answer:

How did Galen discover more about how the human body worked? He conducted animal dissections and made clinical observations.
What limited Galen's understanding of the human body? Lack of human - dissection and limitations of contemporary scientific knowledge and technology.