Here are the first four:
1. The extreme fragility of human culture, civilization. A man becomes a beast in three weeks, given heavy labor, cold, hunger, and beatings.
2. The main means for depraving the soul is the cold. Presumably in Central Asian camps people held out longer, for it was warmer there.
3. I realized that friendship, comradeship, would never arise in really difficult, life-threatening conditions. Friendship arises in difficult but bearable conditions (in the hospital, but not at the pit face).
4. I realized that the feeling a man preserves longest is anger. There is only enough flesh on a hungry man for anger: everything else leaves him indifferent.