Bahnsen’s implication that “... man at the center of the knowing process...” is somehow inadequate or erroneous is a strange perspective. Here’s why I think so:
The issue is not what the unbeliever can do intellectually, but whether he can give an account of it (epistemologically) within the worldview he has advocated or espoused. Because all autonomous perspectives take man’s interpretation of the world to be “original”-to be the primary ordering of particulars or “rationalizing” (making systematic sense out of) the brute facts, it puts man at the center of the knowing process-and pays the price for doing so by slipping in subjectivism and skepticism ultimately (when consistent and driven to the logical outcome of his presuppositions
“Brute facts”. Without man around to perceive, interpret and have discourse on his perceptions and interpretations of those perceptions, brute facts are all there is. There may be animals capable of forming primitive interpretations of how and why what they perceive is as they perceive it, but we don’t know that today, and we can't have discourse with them on these subjects today. Consequently, we appear to be justified in asserting that we humans are the only ones that can reason. If we’re not around to reason - to know about things - then what you are left with is spacetime, matter, energy and the forces that act on them. You are left with brute facts. At time T=x, the observable universe of spacetime, matter, energy and the forces that act on them are arranged in a certain way - a “state”. At time T=x+1, that state has changed. There's no rational discussion to have about the first state, the second state, or how and why the two states are different, or how and why they came to be different. There are no rational beings to have the discussion.
As beings that have arisen in this universe, and have (arguably) minds that are capable of perceiving, interpreting and reasoning, what we humans can do is wonder about how we came to having those capabilities. This is where Dr. Bahnsen commits some egregious errors. He assumes that because he has no physical explanation for human reasoning, that a non-physical, supernatural explanation is adequate. He doesn’t have an explanation for that non-physical, supernatural explanation, he just asserts that it is the explanation. There is no good reason to accept this assertion - none. Depending on where and how you analyze an assertion like this, Dr. Bahnsen can be shown to commit a bare assertion fallacy, an argument from ignorance, special pleading, and probably others.
I'm beginning to think presuppositional apologetics is indicative of a personality flaw as much as it is an indication of a flaw in reason.
That’s as snarky as I need to get today.