In accepting the Republican nomination for the US Senate in 1858 Lincoln presented a particularly eloquent version of the Republican argument against the extension of slavery. Once again he makes the case against the argument advanced by his opponent, Senator Stephen A. Douglas, that the people (i.e., enfranchised white males) should decide democratically whether their state will enter the Union as a free or a slave state. In practice, Douglas’s doctrine of Popular Sovereignty would perpetuate the primary division within the “house” that is the American republic, and “a house divided against itself cannot stand.”

Mr. President and Gentlemen of the Convention,

If we could first know where we are, and whither we are tending, we could then better judge what to do, and how to do it.

We are now far into the fifth year, since a policy was initiated, with the avowed object, and confident promise, of putting an end to slavery agitation.

Under the operation of that policy, that agitation has not only, not ceased, but has constantly augmented.

In my opinion, it will not cease, until a crisis shall have been reached, and passed.

A house divided against itself cannot stand.

I believe this government cannot endure, permanently half slave and half free.

I do not expect the Union to be dissolved – I do not expect the house to fall – but I do expect it will cease to be divided. It will become all one thing, or all the other.

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