When you say Christians are delusional because they place faith in an invisible Being I query how well your belief system can make sense of why you exist? If you do not care to question this then you are left with your facts and the present alone. Nothing else can be known, or so you seem to believe.
So unless I make assumptions about things I don't actually know to be true, I can't know those things? I guess you've never heard of scientific research? Please carefully read what I'm about to say.
Whether you want to think of it or not humanity got here somehow. Whether you know or not your atheistic worldview is impacted. The universe and you are here due to one of a few possibilities. I would argue two main contenders; chance or Creator. Other beliefs are not reasonable. Of atheism or theism, which is more logical and reasonable to believe? Your worldview being right/true depends on whether or not you are right about origins. That is the simple explanation. So, if you want to hold to atheism without considering the truth of your belief system that is your choice. Thus, it matters greatly how we got here. If God is true and every man a liar (
Romans 3:4), you have a problem.
You make assumptions about things you don't know to be true whether you are aware of it or not just by the choice of your worldview: atheism. There is no getting around that. You accuse Christians of being delusional because you see no evidence of God. I ask, where is the evidence that the atheistic view of origins of the universe and life is true, which means not my belief but yours could be the delusional one because your belief at present is hinged on the idea of naturalism or materialism. That is how you go about proving things, through a naturalistic perspective.
Looking at the universe, the world, life, human nature, etc. You see it through naturalistic eyes alone.
Greg Bahnsen expounding on Van Til put it this way:
"Whenever we are drawn into a defense of the faith, Van Til observed, there is a dispute between two different ultimate commitments - a conflict between final authorities for living and reasoning. Neither side can be neutral, and the unbeliever's bias will be evident by his opposition to any authority that does not leave him autonomous." Van Til Apologetics, Reading and Analysis, by Greg Bahnsen, p. 700.
So, you and I disagree on the nature of truth, meaning, evidence, and the source of our knowledge, you being an atheist and I being a Christian. Van Til argued, as an atheist, you have a prejudice against God. The Bible argues the same proposition (i.e., Romans 1:18-28).
"If God exists and is as the Christian worldview claims, then His existence has an undeniable bearing on how we understand the process of knowing, the standard of truth and evidence, ultimate authority, and other crucial matters of epistemology." Van Til, p. 146.
Thus, as an atheist, you have committed to a specific and particular kind of thinking. Your mind operates not in a neutral fashion but with a particular bias and predispositions towards that mindset. Your mindset interprets the world strictly through a naturalistic process.
Bahnsen continues to extrapolate on Van Til's thoughts, about the problem of knowledge and how some philosophers see the problem of how "a finite mind can have a wide enough (inclusive enough) system to know any particular or limited truth....while [awaiting] progress towards more adequate integration of the various aspects of what we know." p. 147.
This is what you expressed above in your statement, "I can't know these things..."
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