Frederick Douglass is the abolitionist known for the motto "The right to know is the right to act." His powerful autobiography and speeches highlighted the inhumane conditions of slavery and advocated for the abolitionist cause. Douglass's emphasis on education and knowledge for enslaved individuals underscored the belief that awareness fosters empowerment and resistance. His relentless pursuit of justice and equality has left a lasting impact on civil rights movements, inspiring generations to fight against oppression and inequality.