On a more mundane level, and leaving the cosmic attitude behind, if my theory of consciousness is correct, any attitude of mind and any intellectual discipline whatever is governed by the unspoken and often unconscious assumptions on which it is based. So if you adopt an attitude of mind that rules out the existence of God and freewill, and consider the physical world and evolution, naturally you will reach conclusions which rule out the influence of God and freewill on what you have observed. I understand that mathematicians hold the view that the axioms on which any mathematics is based can lead to absurdity, if they are not sufficiently related to experience. My theory simply says that it is the same in any intellectual discipline. Your underlying assumptions must be sensible, for your attitude to be sensible. So when people say we are all pre-programmed by our Genes, they are in principle saying much the same as Thomas Aquinas. They are assuming before they begin, what they then set out to prove. Nothing necessarily wrong in that, provided you realize your proofs are only persuasive proofs; not rigorous proofs. It is ignorant not to understand this.
In conclusion, I think you can destroy the validity of peoples’ prejudices or beliefs, by invalidating the whole attitude of mind that those people have adopted. But if the attitude of mind is valid, then you can only destroy those prejudices and beliefs by argument from within that attitude of mind. To seek to destroy religious belief by arguing from the attitude of mind of a biologist, who discounts entirely religious belief, is as foolish as to try to rubbish biological beliefs by reliance on the Bible, which whatever anybody says is a wonderfully inspired book but hardly a textbook on biology. To anyone who is interested in the workings of the human mind, I would recommend Clausewitz’s On War. He spent his whole life in the army, he was an Ensign at Valmy, and a Major-General by the end of his career; and he knew only too well the human desire to make facts fit one’s preconceived opinions. And I reckon the heart of his teaching about the human mind is that Rules, whether they are the outward Rules of conventional theory, or the inner Rules of habitual thought, exist to guide judgement and discretion: not to control judgement and discretion. So judgement is supreme. You must make up your mind either to believe in God, or deny there is a God; and you are unwise if you think that any proof that He does exist, or does not exist, is worth much.
Besides, you do not want proof; you want trust. One of the most remarkable incidents in the Alamein campaign was the meeting between Lieut. General Montgomery and Brigadier de Guingand at a cross-roads on the edge of the desert, early in the morning of the 13th August 1942. Brigadier de Guingand was considerably younger, but they knew each other well, having met first in about 1932.