"The Free State men, myself among them, took it for granted that Missouri was a slave state."

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I hold it to be a paramount duty of us in the free states, due to the Union of the states, and perhaps to liberty itself (paradox though it may seem) to let the slavery of the other states alone; while, on the other hand, I hold it to be equally clear, that we should never knowingly lend ourselves directly or indirectly, to prevent that slavery from dying a natural death--to find new places for it to live in, when it can no longer exist in the old.

— Abraham Lincoln