In this new consideration of Lincoln s public philosophy the nation s understanding of itself Sands seeks to determine why the spirit that successfully led the Union through the Civil War was unable to sustain itself during Reconstruction. He defines Lincolnism as a rededication to the principle of natural rights, a narrative of Divine Providence, a sentiment of brotherhood, and an augmentation of founding principles. He then explains how Lincoln s assassination, Johnson s succession, and developments in philosophy and science worked to undermine this philosophy after the war.