Wgat decision do Sam and Haley discuss?

They discuss the decision of waiting to leave until after dinner.

"Why, Mas'r," said Sam, in a deprecating tone, "I believe you mean to kill us all clar, horses and all. Here we are all just ready to drop down, and the critters all in a reek of sweat. Why, Mas'r won't think of startin' on now till arter dinner. Mas'rs' hoss wants rubben down; see how he splashed hisself; and Jerry limps too; don't think Missis would be willin' to have us start dis yer way, no how. Lord bless you, Mas'r, we can ketch up, if we do stop. Lizy never was no great of a walker."