A person intentionally renders a colleague's kosher food ritually impure. The food looks the same but is now forbidden. What is his liability?
Halachah 1–2: By Scriptural law, non-evident damage is exempt. However, the Sages imposed a Rabbinic penalty of full damages from best property to prevent people from deliberately causing invisible damage.
Question 2
Reuven sells a promissory note to Levi, then forgives Shimon's debt (the original debtor). What is Reuven's liability?
Halachah 10: By forgiving Shimon after selling the note to Levi, Reuven caused Levi to lose the debt. He is treated as if he burned the note and must pay Levi the full amount.
Question 3
A person throws a utensil from a roof with no cushion below. Before it hits, a bystander smashes it mid-air with a stick. Is the bystander liable?
Halachah 12: The bystander is exempt — he broke a utensil that was already about to break with certainty. Breaking a broken object creates no liability.
Question 4
A damager throws the victim's wallet into the sea without knowing what was in it. The victim claims it was full of gold coins. What is the process?
Halachah 17: By Rabbinic enactment, the victim takes an oath (sh'vuat hesset while holding a sacred object) and collects the amount claimed — provided the claim is plausible (i.e., it is normal to carry gold coins in a wallet).
Question 5
Someone cuts down a neighbor's dangerous tree without permission, before the owner could do so himself. Must he pay the owner?
Halachah 13: One who preempts the owner's mitzvah by cutting his condemned tree without permission is liable to pay the owner as determined by judges — he prevented the owner from performing the mitzvah himself.