Rabbi Dayan welcomed Mr. Mann and Mr. Wolf into his office.

“What brings you here?” he asked them.

“Mr. Wolf sent me a computer virus as an e-mail attachment,” said Mr. Mann. “Supposedly, the file was a ‘helpful computer program,’ which he said to install. The file was a virus, though; when I clicked on it, it attacked my computer! Removing the virus and getting Windows to work again cost $250. I think that Mr. Wolf should pay for the repair.”

“Did you know that the file was a virus?” Rabbi Dayan asked Mr. Wolf.

“No,” replied Mr. Wolf. “I simply forwarded the e-mail without examining it.”

“Infecting a computer with a virus is considered doing damage,” said Rabbi Dayan. “However, there are two issues here that need to be clarified. To illustrate, let me share with you another question that came my way.”

The two men listened intently.

“A person put some poisoned food in front of his neighbor’s animal,” Rabbi Dayan said. “The animal ate the food and died. The owner sued the neighbor for killing his animal. What do you say about this case?”

“I would say he’s liable,” said Mr. Wolf. “He poisoned the animal.”

“I’m not so sure,” objected Mr. Mann. “The neighbor didn’t actually kill the animal. Although he put out the poison, the animal chose to eat the food.”

“Animals don’t exactly have choice,” reasoned Mr. Wolf. “If they see food, they eat! Anyway, even if the neighbor didn’t directly kill the animal, he certainly brought about the animal’s death.”

“But is that enough to hold him liable?” argued Mr. Mann. He turned to Rabbi Dayan.

“The Gemara (B.K. 47b; 56a) teaches that placing poison before an animal is considered grama,” answered Rabbi Dayan. “The animal did not have to eat the poisoned food. Therefore, the neighbor is not legally liable in beis din, but he is responsible b’dinei Shamayim. This means that he has a strong moral liability to pay, albeit not enforceable in beis din (Shach 386:23; 32:2).”

“I still don’t understand,” said Mr. Wolf. “Since the neighbor expects the animal to eat the poisoned food, why isn’t there a full legal liability?”

“The truth is, the Rosh indicates that the person is exempt only if it was unusual for the animal to eat,” explained Rabbi Dayan, “for example, if the poison was not regular food or if the animal overate. However, Tosafos indicates that even if the poison was mixed with regular food, since the animal brought the injury upon itself through its intended action of eating, we cannot obligate the person.”

“What does all this have to do with our case of a virus attachment?” asked Mr. Mann.

“In the typical case, e-mail viruses are not self-opening,” explained Rabbi Dayan. “Although Mr. Wolf sent you the computer virus, you had to click on it in order to activate the virus! Many contemporary authorities compare this to placing poison before the animal. Just as in the latter case, it is not possible to impose a legal liability because the animal chose to eat the food and brought the damage upon itself, so too, you chose to click on the file and thereby activate the virus.”

“So where does that leave us?” asked Mr. Wolf.

“Our case, similarly, is only one of grama, like placing poison before the animal,” said Rabbi Dayan. “Therefore, it is not possible to impose a legal liability on Mr. Wolf (see Mishpetei HaTorah, B.K. #67; Shimru Mishpat 2:71).”

“What about a chiyuv b’dinei Shamayim?” asked Mr. Mann.

“In addition to the fact that Mr. Wolf simply forwarded the e-mail with no nefarious intent, there is another factor to consider,” concluded Rabbi Dayan. “People nowadays are aware of computer viruses and of the need to be careful when opening attachment files, especially with .exe endings. An outdated or free version of anti-virus often does not provide full protection. Therefore, there was also an element of neglect on Mr. Mann’s part.

“Thus, in this case, Mr. Wolf would be exempt even b’dinei Shamayim.”

The gabbai in our shul sells hadassim (myrtle branches). Occasionally, he leaves his eleven-year-old son in charge.

It occurred to me that it might be problematic to purchase hadassim from his son, since mi’d’Oraisa (according to the Torah) a child cannot buy or sell things.

Q: Is it a problem for me to purchase hadassim from this boy?

A: The Torah mandates that a person must be the halachic owner of his four species. The mitzvah cannot be fulfilled with stolen - or even borrowed - species. Therefore, since a child cannot execute proprietary acts (kinyanim), one should not be able to fulfill the mitzvah if even one of the four species was purchased from a minor.

Although Chazal instituted proprietary acts for minors in limited circumstances, nevertheless, that proprietary act is effective only on a Rabbinic level and should not be effective when one must satisfy a Biblical obligation (O.C. siman 658:6).

The truth is, however, that this question is not related to the validity of a minor’s proprietary act. It is obviously the child’s father who is the seller, and his son is merely his agent to execute the sale. The question that must be addressed is whether a child may serve as an agent to execute a sale.

At first glance, it seems that a child may not serve as his father’s agent to sell hadassim since, as a rule, children may not serve as agents (C.M. 188:2).

Upon further analysis, however, there is no issue if a child sells his father’s hadassim. A child may not serve as an agent when his input is necessary for the kinyan to be valid, e.g. a purchaser asks a child to take physical possession of an object on his behalf, or a merchant gives merchandise to a child to sell and gives the child discretion to decide how much he wants to charge for the merchandise.

If a merchant asks a child to deliver merchandise to a customer and the customer takes possession of the merchandise from the hands of the child, the kinyan between the merchant and the customer is valid. In this capacity, the child is merely acting as a deliveryman and plays no role in the actual kinyan (Nesivos 182:2 and 244:1).

Accordingly, if the gabbai set the price per hadas or per set of hadassim and the child is merely collecting the money for his father, the sale is effective even on a Biblical level. It is no different from the gabbai leaving hadassim on a table with a sign that states a fixed price for each hadas or set of hadassim. Even though the seller is not present at the time the customer puts down the money, the transaction is certainly valid, and having a child collect the money is certainly not worse than no one being present at the time of the sale (Sefer Chanoch Lanaar 25[8]).

Q: I found a single shoe in my shul. Must I publicize and try to return it?

A: The minimum value of hashavas aveidah is a perutah, a coin worth .025g (1/1,000 oz.) of silver. At current silver prices, this is a penny or two. Thus, almost all items have this value.

However, this minimal value must exist both at the time of loss and at the time of finding. Thus, food that spoiled and no longer has any value is not subject to hashavas aveidah (C.M. 262:1). Furthermore, some Poskim maintain that the perutah value is determined by the item’s market value (Nesivos 148:1). A single shoe is worthless on the market.

Nevertheless, many contemporary Poskim (Chazon Ish, Harav M. Feinstein and Harav Y. S. Elyashiv, zt”l) maintain that the item’s value is determined by its owner. Thus, even a single shoe is of value to him, to pair with the other shoe that he has not lost. Therefore, you should try to do hashavas aveidah with the shoe (Hashavas Aveidah K’halacha 1:7).

The same halacha applies to something like a family photo, which has no market value, but is valuable to its owner.