Grounds?
Arnie, the tailor was frantic. His wife, Rebecca, was sick and perhaps dying.
"Doctor, please save my wife. I'll pay anything."
"What if I can't cure her?"
"I'll pay you whether you cure her or kill her. Just come straight away."
Although the doctor was prompt in visiting the woman, she died a few days later.
The doctor sent Arnie a hefty bill. The tailor couldn't hope to pay, and asked the doctor to appear before the rabbi with him, to have the case arbitrated.
"He agreed to pay me for treating his wife, whether I cured her, or killed her."
The rabbi asked thoughtfully,
"Well, did you cure her?"
"No."
"Then did you kill her?"
"Certainly not."
"In that case," said the rabbi, "you have no grounds on which to base a fee."