Armstrong: For the treatment of a particular disease, Dr. Sullivan argues for using nutritional supplements rather than the pharmaceuticals that most doctors prescribe. But this is in his self-interest since he is paid to endorse a line of nutritional supplements. Thus, we should not use nutritional supplements in treating the disease. Armstrong's argument is flawed in that it ['relies solely on an appeal to an authority whose trustworthiness should not necessarily be taken for granted', "appeals to people's emotions regarding the treatment of disease rather than to the efficacy of the two approaches to treatment", "criticizes Dr. Sullivan's motives for holding a position rather than addressing the position itself", 'fails to justify its presumption that nutritional supplements cannot be used in conjunction with other treatments']