1) A SON WHO INJURES HIS FATHER IN A WAY THAT OBLIGATES HIM TO PAY THE DAMAGE PAYMENTS
QUESTION: The Gemara attempts to prove from the Mishnah later (87a) that one must pay Nezek to his victim when he causes a temporary wound which will heal completely. The Mishnah discusses a person who hit his parents but did not make an open wound. The Mishnah rules that such a person is exempt from a Chiyuv Misah and must therefore pay all five of the damage payments. The Gemara reasons that the only case of damage that one might have caused without making an open wound, which would still make him obligated to pay, is a case in which the son hit his parent and caused a bruise that did not bleed externally, and that will eventually heal completely.
Why does the Gemara understand that this must be the case of the Mishnah? Why does the Gemara not explain that the Mishnah refers to a case of permanent damage, such as where the son hit the father on the hand in a way that caused it to become partially paralyzed ("Tzamsah Yado") in a manner that will not heal. In such a case the son would not be Chayav Misah since the father lost no blood, but he would be obligated to pay the damage payments since he caused permanent damage to his father! (RASHBA)
ANSWER: The RASHBA answers that in any case where the father suffered permanent damage, it is assumed that there must have been some internal bleeding that caused it, so the son is Chayav Misah. The Rashba's reasoning is based on what the Gemara says about a son who causes his father to become deaf. The Gemara says that it is impossible for the father to become permanently deaf without internal bleeding in his ear, and thus the son is Chayav Misah for his act. The Rashba understands that the same applies in any case of permanent damage.
This also appears to be the intention of RASHI (DH Lav).
2) UNEMPLOYMENT COMPENSATION FOR ILLNESS CAUSED BY A TEMPORARY INJURY
QUESTION: Abaye and Rava argue about the payment of Nezek in a case of a person who causes temporary damage to the body of another person. Abaye rules that one pays Nezek and Sheves, as in any case of damage done to someone else.
Rava rules that no Nezek is paid in such a case due to the temporary nature of the damage. The lack of Nezek payment directly affects the amount of Sheves that is paid. Since no Nezek is paid, the payment of Sheves cannot be based on the wages of a Shomer Kishu'im (gourd-guard), since that calculation applies only when the victim is already being compensated for the loss of the use of his hand. Consequently, the Sheves is paid on a daily basis, based on the wages that the victim could have earned on that day through his regular vocation had he not been ill.
Why, according to Abaye, is the Sheves calculated according to the wages of a Shomer Kishu'im? After all, RASHI (DH d'Va'i Achuyei) explains that if the damage does not prevent the victim from returning to his previous occupation once he has recovered, the payment of Sheves is not determined by the wages of a Shomer Kishu'im but by the wages that the victim will receive after his recovery. A person who suffered temporary bodily damage will certainly be able to do the same Melachah upon recovery as he did before the injury. Why, then, does Abaye not agree with Rava's ruling that the Sheves is determined based on the wages that he would normally earn? (See MAHARSHA in Mahadura Basra.)
ANSWER: In the case which Rashi discusses (in which a person damages someone by causing him to become permanently bald), the Nezek payment that the Mazik pays is not meant to compensate for the temporary loss of work as a jester resulting from the sores on the victim's bald head. Rather, the payment of Nezek is meant to compensate for the victim's depreciation in value due to his unsightliness (see Rashi, DH Nasha). Therefore, the Sheves payment must take into account the entire loss due to his lack of work during the time until his sores have healed. However, in the case in which a person temporarily disables another person's hand, there is no depreciation due to unsightliness. The Nezek which Abaye obligates the Mazik to pay is a compensation for the fact that the victim cannot work with his hand for a few weeks. Since the payment of Nezek already accounts for the loss of the victim's normal use of his hand, the payment of Sheves needs to cover only the loss that the victim would have incurred had he been a Shomer Kishu'im during that time.
However, if it is true that the payment of Nezek (according to Abaye) takes into account the depreciation due to the victim's temporary inability to work, then why does Rava disagree with Abaye? Since there is a clear depreciation in value due to the temporary disability, it should be paid as Nezek, like any other depreciation in the value of the victim!
The TOSFOS RABEINU PERETZ asks this question. He answers that the depreciation that results from the fact that people will pay less for him (as an Eved) since he is temporarily disabled is greater than the actual loss the victim suffers from being unable to work during the days of his disability. The reason for this is that not every potential purchaser in the market can evaluate clearly whether the disability is indeed temporary, and, if it is temporary, how long it will last. Therefore, a purchaser would not offer to purchase the slave for his true value, but only for less than his true value. Consequently, Rava says that it is not fair for the Mazik to have to pay Nezek based on the victim's lower market value, and it suffices to pay the daily Sheves for the duration of time that the victim actually cannot work. This is also the intention of TOSFOS (85b, DH Sheves).

86b----------------------------------------86b

3) A BLIND PERSON'S OBLIGATION TO PAY FOR DAMAGES
QUESTION: Rebbi Yehudah rules that a blind person who embarrassed another person is exempt from the payment of Boshes. He derives this from a Gezeirah Shavah which compares the payment of Boshes to the punishment of Edim Zomemim. RASHI explains that a blind person can never be punished as an Ed Zomem, since he cannot testify about something he did not see.
REBBI AKIVA EIGER (in Gilyon ha'Shas) asks, why can a blind person not be punished as an Ed Zomem for testifying about what he saw before he became blind? In such a case, a blind person's testimony should be accepted, and thus he should be able to become an Ed Zomem. Since the Torah compares the payment of Boshes to the punishment of Edim Zomemim, a blind person should also be liable for the payment of Boshes.
ANSWER: Perhaps Rashi understands that according to Rebbi Yehudah, if a person embarrasses his friend and afterwards becomes blind, he indeed is obligated to pay Boshes. Hence, the comparison to Ed Zomem is correct in both cases. A person cannot testify about something that happened while he was blind (and become an Ed Zomem for such testimony); similarly, a person cannot be obligated to pay Boshes for embarrassing someone while he was blind. Moreover, just as a person can become an Ed Zomem for testifying about an act he witnessed before he became blind, so, too, a person can become obligated to pay Boshes for an act he committed before he became blind.
Rebbi Akiva Eiger may have found this answer unsatisfactory in light of the Gemara later (beginning of 87a). The Gemara teaches that according to Rebbi Yehudah, a blind person is exempt not only from Boshes but from all of the payments mentioned in the Torah, and he is not obligated to observe any of the Mitzvos of the Torah. The logic of this ruling seems to be that Rebbi Yehudah compares a blind person to a Cheresh or Shoteh to some extent. Hence, if a person is blind at the time that he appears before the court, the court should not be able to obligate him to pay even for actions he performed before he became blind, just as Beis Din cannot obligate a Cheresh or Shoteh for acts he performed before he became a Cheresh or Shoteh. Thus, he would not be obligated to pay Boshes even for embarrassing someone before he became blind.
Rashi, on the other hand, perhaps follows the view of TOSFOS. Tosfos (87a, DH v'Chen) asks why Rebbi Yehudah must derive from a Gezeirah Shavah that a blind person does not pay Boshes if he has another source which teaches that a blind person pays no payments. Tosfos answers that Rebbi Yehudah originally exempted a blind person only from Boshes, based on the Gezeirah Shavah. Later, he found another verse that exempts a blind person from all payments, and he no longer derived the exemption of Boshes from the Gezeirah Shavah but from the second verse, along with the exemption from all other payments.
According to this answer of Tosfos, the exemptions derived from the two verses are not identical. The first verse teaches that a blind person is exempt only from Boshes payments that are incurred as a result of an act that the blind person did after he became blind. This is logical, since this verse differentiates between a blind person and other people only with regard to Boshes. The unique exemption from Boshes is probably because a person suffers less embarrassment from an act done by a person who cannot see him and is not fully aware of the damage that he is causing. Therefore, it is logical to assume that the factor that determines whether or not a blind person pays Boshes is whether he was blind at the time that he caused the damage. In contrast, when Rebbi Yehudah changed his mind and compared a blind person to a Cheresh or Shoteh, he exempted a blind person from all payments, regardless of when they were incurred. (M. KORNFELD)

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