Let's say you have been promoting some view (on some complex or fraught topic – e.g. politics, religion; or any "cause" or "-ism") for some time. When somebody criticizes this view, you spring to its defense. You find that you can easily refute most objections, and this increases your confidence. The view might originally have represented your best understanding of the topic. Subsequently you have gained more evidence, experience, and insight; yet the original view is never seriously reconsidered. You tell yourself that you remain objective and open-minded, but in fact your brain has stopped looking and listening for alternatives.