"When the facts change, I change my mind".
Agreed.
Projection is not reality.
Agreed.
Facts are absolute and do not change. Circumstances and context change in which the interpretation of facts may rightly vary.
That is true, but incomplete. The set of facts pertaining to a given case may change as new information becomes available, and in the face of such a change, an honest man will necessarily amend his view. That is what I understand Keynes to have meant by his words.
Integrity persists--or loses. Character matters.
Character strives to discern absolute truth and act accordingly.
I agree with this also, but it seems to me that you and I are talking about two different aspects of the way in which one should approach Truth. (Capitalization used to distinguish absolute Truth from perceived truth).