Human reason allow the creature to do at least that.
But most of us accept such a mere understanding in the unregenerate. I have not read much of what you have been reading, but I wonder if, among other things, he is combatting the tendency in parts of the Reformed world to do little preaching or speaking on the subject of the gospel to the lost man. Dr. Bahnsen also does not allow Van Til's message to be buried under an Everest of philosophical jargon. He trumpets Van Til's call for regeneration. He cites Van Til's assertion that man is spiritually dead and that there are no degrees of deadness.