Putting your point in the article's terms, I think you're saying that the knowledge of our existential condition is always limited. As I said, the secular account of that condition is based on history, philosophy, and science, but none of those disciplines can see far into the future.

That's true, which is what lends so much weight to the existential choice we nevertheless make. We make it partly in the dark, gambling on our limited knowledge. That choice or foundational attitude we have is partly a leap of faith.