Justin Martyr posted a new response to me over on his blog. He basically thinks that his personal experience of God is the same as his personal experience that he ate an egg sandwich.
I disagree. First of all, if we wanted we could take a poll and establish about how many people eat egg sandwiches for breakfast. Let's say that it is .1%. So the initial probability is about .1%. But how often do people hallucinate eating some breakfast? I would suppose that it would be much less than .1%. How many people are mistaken about what they ate for breakfast? I would suppose very few, especially if they were given time to recall, and if they vividly recalled their breakfast this morning. Therefore, you could conlude that they had an egg sandwich, because it is the most probable explanation for the data.
Now, why is this different from subjective assertions? For the reason that I outlined in my last post:
Seeing a tree is not quite the same as feeling the 'inner witness' of the Holy Spirit. For one thing, we can all see the tree. Even if someone was raised in a place where there were no trees, you could still show them a tree (though they would not know what to call it). Furthermore, dowsers, psychics, and alternative medicine gurus often truly believe that they have powers, but we obviously know that they are wrong, so subjective beliefs about objective reality are simply irrelevant and not valid guides to it. I suppose you could say that the psychics, alternative medicine gurus, and dowsers are lying for money, but I don't think that's true. Have a look at "The Enemies of Reason" with Richard Dawkins and see for yourself whether these people are worrying about financial gain (or are insincere). Better yet, take a look at all the studies on placebos that have been done.
The inner witness of the Holy Spirit is not quite like seeing a tree because most people who were not raised Christian do not have it. The cultural context in which someone grows up and lives in almost always predicts what their inner feelings about religion are. And of course most culturally specific beliefs (meaning not held by most human beings the world over, but only in certain cultural contexts), at least the ones concerning religion, are false. The fact is that if you had been raised in India, Saudi Arabia, or Europe (before the 4th Century) you would very probably not have any inner witness of the Holy Spirit. Maybe an inner witness of Allah, or Krishna, or Hercules, or Aesclepius, but almost certainly not the Holy Spirit. Since we can see that subjective feelings about God are strongly correlated with culture, and most cultures have to be wrong, then this type of feeling is not a valid type of evidence for God because it is usually wrong.