The American freethought movement advocates for the use of reason and critical thinking in understanding the world, often challenging religious dogma and superstition. It promotes the idea that beliefs should be based on evidence and rational inquiry rather than tradition or authority. This movement has roots in the Enlightenment and has influenced various social and political reforms throughout American history. Key figures in the movement include Thomas Paine, Robert Ingersoll, and Margaret Sanger, who emphasized individual liberty and the importance of secularism in public life. The movement has contributed to the growth of secular humanism and the separation of church and state in the United States.