If one who finds a lost item does not want to lose out on getting compensated for their full wages while attending to the lost item, one can stipulate this in front of a court (three men) and then the one who lost the item will need to compensate the finder the full amount. Raba bar Rav Huna wanted to apply this law to a case where Rav Safra took his half of a shared business deal in front of witnesses, but not three men.  Rav Safra rejected this proof, but Abaye brought proof from a different source that indeed Rav Safra was required to divide the money in front of three men. If one finds an animal in a cowshed, it is not considered a lost item but in a public thoroughfare, it is. Is this within the borders of the city or outside the borders? If one's parent tells one to do something against what the Torah commands, one cannot listen to the parent. For example, if a parent tells their child not to return a lost item, the child must disobey the parent. This is derived from Vayikra 19:3 where the commandment to fear one's parent is followed by a commandment to keep Shabbat. Rabbi Shimon and the rabbis have a debate regarding the laws of helping another to load a burden - can one demand compensation for lost wages or not? What is the basis of the debate? Both would agree however, that theoretically one could have derived laws of unloading from laws of loading from a kal v'chomer argument. Rava tries to derive from this that the mitzva of tzaar baalei chayim, the commandment to prevent suffering to animals is a Torah law, as the kal v'chomer argument would be that if one is obligated to help load, when there is no suffering to the animal, kal v'chomer they are obligated to unload, where the animal is suffering. This is rejected as the kal v'chomer argument could be based on the fact that loading does not involve a financial loss and unloading does. But then the Gemara rejects that, as in loading, there is also a financial loss. Various sources are brought to determine if Rava is correct in assuming that tzaar baalei chayim is a Torah law.