I have had undeniable personal revelation, and I know there is a God. You may say I'm deluded, and you may even be right. But at best, you can only call THAT an opinion. I may or may not know there is a God. You certainly do not know whether or not I know.
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How about Indians who have seen Lord Krishna, Ganesh or some other Hindu deity? People get visions all the time. Protestants see Jesus, Catholics see the Blessed Virgin, Buddhists, Hindus, Farsees and pagans see apparitions with surprising regularity. People claim to have been abducted by Grey aliens, probed, and returned. Everyone has to decide based on faith alone, what to make of such events, don't they. I can only admit that you have experienced something that YOU think is real and YOU think you 'know'.
If I see you stop fopr a stop sign, and you say you know you stpopped for it, then I can safely say that I agree that you 'know' this. Any other affirmations about what you 'know' are conjecture and you claiming to know what happened is valid for you to say, but not for me to affirm.