The greatest human talent is self-delusion. (Often propped-up by another, our penchant for self-righteousness.) Across recorded history, delusional leaders were responsible for countless horrific errors of statecraft, though it was common folk who suffered. Yet, ruling castes always made it their top priority to limit criticism, the only thing that might have corrected their mistakes. This dire contradiction propelled much of the tragedy of the last 4,000 years. (http://www.davidbrin.com/addiction.htm)
Author David Brin, found here.