Here are Lincoln's last words on the subject from the 6th debate. I find them, and his other responses, entirely satisfactory.
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Judge Douglas, in reply to what I have said about having upon a previous occasion made the speech at Ottawa as the one he took an extract from, at Charleston, says it only shows that I practiced the deception twice. Now, my friends, are any of you obtuse enough to swallow that? [``No, no, we're not such fools.''] Judge Douglas had said I had made a speech at Charleston that I would not make up north, and I turned around and answered him by showing I had made that same speech up north---had made it at Ottawa---made it in his hearing---made it in the Abolition District---in Lovejoy's District---in the personal presence of Lovejoy himself---in the same atmosphere exactly in which I had made my Chicago speech of which he complains so much.
Now, in relation to my not having said anything about the quotation from the Chicago speech: He thinks that is a terrible subject for me to handle. Why, gentlemen, I can show you that the substance of the Chicago speech I delivered two years ago in ``Egypt,'' as he calls it. It was down at Springfield. That speech is here in this book, and I could turn to it and read it to you but for the lack of time. I have not now the time to read it.
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Douglas is quibbling, and Lincoln was utterly consistent on this matter from Peoria to Chicago, from 1854 to 1858.
There are illuminating discussions of the whole question of equality in Jaffa's "Crisis of the House Divided," [Ch. 17] and Miller's "Lincoln's Virtues" [Ch. 14]. Miller concedes more than does Jaffa, but both agree that Lincoln maintained Declaration Principles in the face of gross race-baiting by Douglas and the Democrats.