http://www.straitstimes.com/singapore/transport/impurities-in-material-caused-cracks-on-mrt-trains
The cartoonist's role is not so much to instruct his audience, or illuminate the Truth, as it is to simply take an honest stand and present it vehemently enough so that it must be confronted. This constitutes the power of the cartoon to stimulate discussion and debate. And this is the cartoon's positive function in society-Bill Watterson
