If Ramesh Ponnuru wants to pose as an authority on Catholicism he should not make a parade of his ignorance of the meaning of “invincible ignorance.” This term is applied by the Church to those who were born before the advent of Jesus, or who live in parts of the world where the news of the Church’s teachings is unknown. It applies, in other words, to those who have never heard of Catholicism. I am not sufficiently fortunate to be of that number: ergo there is at least in this case nothing invincible about me.