I can speak of slavery only so far as it came under my own observation - only so far as I have known and experienced it in my own person.
Frederick Douglass, Sojourner Truth, Solomon Northup, Olaudah Equiano (2016). “Slave Narratives Compilation: Twelve Years A Slave, My Bondage and My Freedom, Narrative of the Life of Frederick Douglass, Narrative of Sojourner Truth: A Northern Slave”, p.330, ShandonPress