These debates were between Abraham Lincoln and Stephen Douglas.
This took place in 1858, one year after the Dred Scott decision.
Douglas accused Lincoln of saying that the US could not survive divided into free and slave states and that he had led a crusade against the peeps who had took part in the Dred Scott Decision. He also accused Lincoln of saying that 'negro's' were equal with white men and that "negro equality was an unalienable right".
What did he say about himself?
He said that he believed the exact opposite of Mr. Lincoln in that "in my opinion, our government can endure forever". Also that our government was established with the decision to allow the states to decide slavery for themselves and that he saw nothing wrong with that. The people have the right to make the laws regarding slavery in their own state.
does he say anything interesting or relevant?
He does talk about how "Your safety and ours depends upon both of us acting in good faith" which is an interesting bit of foreshadowing because the Northern and Southern suspicions of each other is what ultimately pushes them to civil war.
He also says that "Abolitionism had even so far divided this country" which ironically enough probably helps to divide the country because it makes the South suspicious of all abolitionists and makes the North defensive.