Ben Stein tells us that evolution leads to genocide. It leads to atheism (which is implicitly bad, apparently). Chaos, murder, cancer, and sad puppies will infest the world if evolution is embraced. It only makes sense then that we should necessarily reject evolution if we want to live in a world of peace and goodness.
Of course, that all sounds utterly silly. But it’s the argument being put forth by Christians all the time (if not in form, then principle): because X leads to something bad, it should be rejected. It is an appeal to emotion. No one wants something bad to be true, so claiming a falsehood on that thing can bring some sort of sense of mind. These people are not ones with which to be reasoned easily.
Emotional appeals are useless in determining what is true. It is the simple truth of something which is important to me. I do not accept or reject evolution based upon an philosophical underpinings or relations. To do so is to make my acceptance or rejection irrelevant and meaningless. If evolution somehow automatically leads to the philosophy of Hitler, that’s unfortunate. That, however, has zero bearing on the truth of evolutionary theory. Either life evolved through small, gradual steps over billions of years of common descent or it didn’t. Nothing Hitler ever thought can change that.
It should not be acceptable for a person to make an emotional appeal on an issue of truth. Save that for the subjectivity of a relationship. We should believe not based upon what we want to believe, but based instead upon evidence. It is evidence which holds so much importance to our lives and to our ability to discern what is true and what is not. Our emotions have no influence over truth.