Photo of Abraham Lincoln taken February 27, 1860 in New York City by Mathew Brady, the day of his famous Cooper Union speech

The following is from Abraham Lincoln’s Cooper Union speech. His call to “duty” is being made to his fellow Republicans, a call to fight the expansion of slavery through their votes.

Neither let us be slandered from our duty by false accusations against us, nor frightened from it by menaces of destruction to the Government nor of dungeons to ourselves. Let us have faith that right makes might, and in that faith, let us, to the end, dare to do our duty as we understand it.

– Abraham Lincoln, Cooper Union speech