X is good because it is natural / occurs in nature / is not man made.  Or, conversely, Y is bad because is not natural / does not occur in nature / is man made.

This fallacy is positively notorious as an advertising ploy. How many times have you seen in a commercial or advertisement — or right on a product package or market signage — that something is “All Natural” or has only “Natural Ingredients?”

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GMO’s get a lot of pushback (“Frankenfoods!”) from certain folks, but let’s face it — if we’re going to resolve some of the world’s hunger issues, GMO’s are not only good, but necessary. And yet, anti-GMO forces have delayed the deployment of foods like golden rice, a GMO rice that contains beta-carotene (precursor to vitamin A). Vitamin A deficiencies are responsible for about a million deaths annually (mostly children) and another 50,000 cases of permanent blindness worldwide.

And yet, because of the fears of “unnatural” GMO’s ginned up by the anti-GMO crowd, deployment of this grain to regions that desperately need it has been stalled for years.