There was once a farmer who wanted desperately to become a doctor like his famous neighbor. He pleaded with his neighbor to take him as a student, but the doctor refused. In those days, it was customary to only teach the medical profession to members of one's own family.

Knowing that the doctor generally taught his family in the evenings after his clinic closed for the day, he secretly hid beneath his window to listen in on the teachings.

That evening, the family conversation went like this: "They've already put off paying for a long time, do you want to charge interest?" The doctor said, "Just collect for the diagnosis and the medicine", "You can forget the interest (suan li k'o chih)".

The farmer, hearing only the last four words of the conversation, misunderstood the doctor as saying "garlic can cure dysentery (suan li k'o chih)", which has the same pronunciation.

It so happened that the farmer's uncle was seriously ill with stomach troubles, so the farmer set off to help him. He gave his uncle garlic to ingest, and sure enough, it worked. The uncle recovered completely.

The farmer stayed at his uncle's house and started a medical practice of curing dysentery. The herbal treatments worked on all his patients and the farmer's reputation spread far and wide.When the famous doctor heard of this, he visited the farmer and said, "I hear you have a cure for dysentery, who taught you?"

"Actually, it was you", replied the farmer, describing the incident under the window.Laughingly, the doctor explained that the comment was about late payment of a patient's bill, not a cure for dysentery. He then said, "It seems you are smarter than I first thought, so I've decided to take you as a student after all".

Although the treatment was based on a misunderstanding, it turned out that it really worked. Garlic has been used in China as a popular medicinal ingredient for many stomach disorders since that time.

—Chinese Folk Tale