You should consider that both positions are unprovable according to the world we live in now. The apostle Paul had this to say about spiritual things: ”
“But a natural man does not accept the things of the Spirit of God, for they are foolishness to him; and he cannot understand them, because they are spiritually appraised.
But he who is spiritual appraises all things, yet he himself is appraised by no one” (1 Co 2:14-15).
Often atheism is created by the world we call “religion” which in most cases does not involve God at all. God is a Spirit and the only way to know Him is through the Spirit which is absent in most denominational churches today. No one can convince an unbeliever that there is a God because the argument ends up in the mind/brain which cannot easily be dissuaded from a position it has adopted.
Again the Apostle Paul said:
“For the mindset on the flesh is death, but the mindset on the Spirit is life and peace because the mindset on the flesh is hostile toward God; for it does not subject itself to the law of God, for it is not even able to do so,” (Romans 8:6-7).
Spiritualism is something one has to experience.
The spirit realm exists just beyond our 5 senses. It is available to everyone but it has to be sought for. There has to be a hunger in an individual that asks “Is this all there is?”. Without spirituality there is no higher purpose to life; no reason for man’s existence.
Solomon, King of Israel and the wisest man of his day said this about the futility of life without God: “Vanity of vanities,” says the Preacher, Vanity of vanities! All is vanity.” What advantage does man have in all his work Which he does under the sun? A generation goes and a generation comes, But the earth remains forever. Also, the sun rises and the sun sets, And hastening to its place it rises there again. Blowing toward the south, All things are wearisome; Man is not able to tell it. The eye is not satisfied with seeing, Nor is the ear filled with hearing. That which has been is that which will be, And that which has been done is that which will be done. So there is nothing new under the sun. Is there anything of which one might say, “See this, it is new”? Already it has existed for ages Which were before us. There is no remembrance of earlier things; And also of the later things which will occur, There will be for them no remembrance Among those who will come later still” (Ecclesiastes 1:2-11).
Conversely, it would be impossible to talk a spiritual person out of his beliefs because he has experienced them personally and, since spirituality is not rational, no rational argument would dissuade him. His belief is based on faith and experience, bot rationality or scientific proof. God made Himself invisible to proof so the spiritual man would walk by faith, even if he does not see the full picture. I guess it boils down to “each his own”. You can lead a horse to water but you can’t make him drink. Works both ways.