Read the passage.
Douglass and Garrison: Two Abolitionists
Frederick Douglass, an African American who had escaped slavery, and William Lloyd Garrison, a white writer who had grown up in the North, shared an important commonality. They were regarded as among the most important abolitionists of their time, and at first they worked together in the fight against slavery. However, as the years passed, Douglass and Garrison came to develop fundamental differences in their opinions about abolition. While Garrison viewed the U.S. Constitution as supporting slavery, Douglass voiced his disagreement with this interpretation. Douglass even argued that the Constitution could be used as a tool to outlaw slavery. In addition, Garrison believed that the Union should be broken up into North and South. Douglass, however, did not want the South to secede from the Union, as he feared that enslaved people would then become isolated in the South. Douglass and Garrison were never able to resolve their disagreements, nor did they ever recover their friendship.
What is the main, or central, idea of the passage?