I’ve encountered people online and in books who claim to be skeptics about historical knowledge. I can’t adopt this position because I know I’ve done bad things. For example I know I ate an ice-cream sandwich last night even though I had promised myself I wouldn’t. If I were a skeptic about history I would not know that I ate the sandwich, and in a sense, I’d prefer not to know it, because it is embarrassing. I also know that people in my family have done bad things — I had a grandfather who was a lawyer for a corrupt union for example. I also know people in my country have done bad things — my nation,the United States, used to be a legally white supremacist state.
So for me the following argument is valid
1)If knowledge of the past were impossible I would not know that I had ever done anything wrong. My conscience would be entirely blemish free.
2)But my conscience is not entirely blemish free — I do know that I have done things wrong (and so have my family and my nation)
3)Therefore knowledge of the past is possible.