We can move a certain amount of stored grain on Shabbos to make room for guests or the teaching of Torah, but we may not move inedible foods. Inedible means something that neither humans nor animals will eat, OR unthithed produce. We discuss the tithing process with the help of slides created by community member Dr. Neil Green. Demai, doubtful produce, may not be eaten until it is tithed after Shabbos but it may be moved because it can be eaten now by the poor, and the homeowner could theoretically vow to consecrate all his property as a donation to the Holy Temple, and thus become poor. Arum is edible only for ravens, which were kept by rich people as pets, so rich people could move arum on Shabbos. Others could not. Even though Rabban Shimon ben Gamliel ruled like Rabbi Shimon and Rabbi Akiva that all Israel are like princes and princesses, the law does not follow their ruling. We may not pick up animals on Shabbos, but we protect them from harm by urging them along to safety. We may even place a cushion or blanket under them if necessary to spare them from pain or distress. This is a big deal because those objects would thereby become a “base for a set-aside object” (the animal) and be rendered set-aside from further use on Shabbos, thus violating the rabbinic prohibition on “negating an object’s preparedness for Shabbos.” We do it because it’s a Torah law to spare an animal from unnecessary pain.