Mr. Hirsch taught Hebrew at the local Jewish day school. In addition, he gave bar mitzvah lessons and tutored neighborhood boys in Jewish studies in the evenings.

Tonight he was booked solid from 6:30 to 9:45 PM, with two lessons at his house and a third in a nearby neighborhood. Thus, when Mrs. Blum asked if he could tutor her son in the evening, Mr. Hirsch had to decline.

At 6:30, Mr. Hirsh settled down for the first lesson. Yaakov was usually prompt, so when he hadn’t arrived ten minutes later, Mr. Hirsh called to find out what was happening.

“Oh, I’m sorry,” said Yaakov. “I have a bad case of strep. I’ve been in bed all week and completely forgot about the lesson.”

Mr. Hirsch wished him well. He usually looked forward to tutoring, but tonight he had papers to grade and didn’t mind some extra time.

Shortly afterwards, Shlomo called. “Hi, Mr. Hirsch. I’m supposed to have a lesson at 7:30, but my friends are getting together tonight. I’ll see you next week.” He hung up before Mr. Hirsch had a chance to respond.

“He could use a little lesson in responsibility and derech eretz,” Mr. Hirsch mused. He immediately notified Mrs. Blum that he now had time available, but she had already arranged with another tutor.

At 8:30, Mr. Hirsch got into his car for the final lesson at Yechiel’s house. While driving, his cell phone rang. “Hello, this is Yechiel’s mother. I apologize, but Yechiel would prefer not to meet tonight.  My brother came over with his kids and Yechiel hasn’t seen them in a while. I hope you haven’t left yet.”

“As a matter of fact, I’m almost at your house,” said Mr. Hirsch. “Is there a chance Yechiel would be willing to learn?”

“I don’t think so,” said his mother. “He’s quite close with his cousins.”

Mr. Hirsch turned around and drove home. He was glad to finish grading the papers, but the loss of all three lessons amounted to a considerable sum. It was particularly annoying because he could have tutored Mrs. Blum’s son had he known ahead of time. Furthermore, he had driven ten minutes to Yechiel before the call came in. Couldn’t people notify him earlier?! He began to wonder whether he was owed pay for any of the missed lessons.

The following night, Mr. Hirsch met Rabbi Dayan at a bar mitzvah. He described the frustrating evening and inquired whether he was entitled to any pay for the lost lessons.

Rabbi Dayan thought for a moment. “It’s fascinating!” he replied. “Your three scenarios parallel three different halachos. The first boy, Yaakov, was sick and unable to come for the lesson. Since he was forced to cancel the appointment he owes you nothing (C.M. 333:1).”

“What about the second boy, Shlomo?” asked Mr. Hirsch. “He could have come for his lesson, but decided to go out with his friends instead.”

“In this situation, it depends whether you were caused a loss by the cancellation,” responded Rabbi Dayan. “Here you turned away Mrs. Blum’s son on account of the expected lesson, so Shlomo owes you for the cancellation. However, since you did not have to spend the time tutoring and had free time to mark your papers, he does not owe you the full amount of the lesson. We call this k’poel batel, like an idle worker, which is approximately half the amount (C.M. 333:2 and Taz).”

“Then I suppose the last boy, Yechiel, doesn’t owe me,” said Mr. Hirsh, “since he didn’t cause me a loss.”

“Actually, he does owe you, since you had already set out to his house,” replied Rabbi Dayan. “This is considered by many poskim as having started the job (SM”A 333:6; Shach 333:7). Once a worker begins, the employer owes him compensation for cancelling willingly, even if it did not cause a loss. Once again, though, since you had the remainder of the evening free to finish grading the papers, he does not owe the full amount. He owes for whatever part of the job was done, and for the remainder k’poel batel.”

“I guess that means I can ask Shlomo for half payment and Yechiel for slightly more,” concluded Mr. Hirsch.

“Correct,” said Rabbi Dayan. “Nonetheless, if there is a clear local practice or stated agreement otherwise, that would supersede these default halachos. For example, many health practitioners have defined rules about notification and cancellation of appointments. Whoever makes an appointment with them does so with that understanding.”