For Lincoln to call upon the Peoria speech is indeed in his own mind a partial explanation of the contradiction. But when viewed in the light of the debate situation in which the comments were made, it becomes inescapable that the contradiction existed externally in Lincoln's own words. Calling upon the Peoria speech was itself an effort by Lincoln to control the blow stricken by Douglas when the latter outed Lincoln on the contradiction. It was damage control on the issue made by Lincoln in a lengthy attempt to soften the blow by running a simple straight forward contradiction in itself through a complex and potentially confusing rhetorical argument. Perhaps in his own mind, Lincoln even rationalized the contradiction as not having been inconsistent at all. But that is Lincoln's own mind. Externally, the contradiction remains.
It might advance things if you were to state, in your own words, what you think the contradiction to be.
Meanwhile, I happily stand by Lincoln's words in Peoria, and my explication of them.
Do you have a copy of either Jaffa or Miller, BTW? That might make things more efficient.
Richard F.