You can't help thinking.

I go to bed after two in the morning, thoughts come and I can't sleep but toss about till dawn, because I think and can't help thinking, just as he can't help plowing and mowing; if he didn't, he would go to the drink shop or fall ill.

Just as I could not stand his terrible physical labor but should die of it in a week, so he could not stand my physical idleness, but would grow fat and die.