We all perceive the world through different lenses. Vischeck helps me understand/anticipate how a red-green colorblind person might see something. Similarly, TNC and BGD good starting points for understanding these other perspectives, and sometimes (I hope) you'll find yourself thinking "I hadn't considered that issue".
Arthur Chu made a lot of important points, including the point that angrily calling "bullshit" doesn't make him wrong (and might sometimes be an effective approach). It's hard to avoid the short term focus of "winning the argument". TNC reflected on this recently - http://www.theatlantic.com/politics/archive/2014/04/race-culture-and-poverty-the-path-forward/360081/ & http://www.theatlantic.com/personal/archive/2014/04/he-hated-error-more-than-he-loved-truth/360329/