Although this bottle is labeled "vinegar, " no fizzing occurred when some of the liquid in it was added to powder from this box labeled "baking soda. " But when an acidic liquid such as vinegar is added to baking soda the resulting mixture fizzes, so this bottle clearly has been mislabeled. A flaw in the reasoning in the argument above is that this argument ['depends on the use of the imprecise term "fizz"', 'assumes that the fact of a labeling error is proof of an intention to deceive', 'fails to exclude an alternative explanation for the observed effect', 'does not take into account the fact that scientific principles can be definitively tested only under controlled laboratory conditions']